Terminated Weapons: Harpoon

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At Fishbreath’s suggestion, I’ve decided to combine some of my resurrection posts with some terminations. Weapons that really should have been cancelled a long time ago, that are in desperate need of replacement. To use a sports metaphor, if I’m calling some up from the minors, I should relegate some others back from the majors. First on the chopping block: the Harpoon antiship missile.

Harpoon has been the western standard antiship missile since its introduction in 1977. It’s got submarine launched, ship launched, and air launched versions, a good active-radar seeker, and you can fit it on most anything. Great. And in the late 70s, it was a good weapon. It gave the warships of the USN some much needed anti-surface punch, and you could retrofit it onto almost any platform.

Looking at it right now, the harpoon sucks.

There are plenty of current market competitors that are better. The harpoon is subsonic; there are plenty of competitors (e.g. SS-N-22 Sunburn and SS-N-27 Sizzler) that are supersonic at least for the terminal phase to reduce reaction time. Is it long ranged? No, the Harpoon is almost painfully short range. Again, the Russians have some really cool long range missiles like the SS-N-19 that have tons of range. Oh, and the Harpoon isn’t stealthy either. Nope.

Let’s make one thing perfectly clear. This isn’t me hating on weapons for not being new. There are plenty of weapon systems that I like that are rather long in the tooth, but have appropriate upgrades to stay current. The C-130, B-52, M-16, and AIM-9 have all received upgrades that keep them useful and competitive with more modern contemporaries. The B-52 and M-16 are particularly good examples of this, having beaten a number of attempts to replace them. There’s nothing wrong with an old weapon per se, but we have to keep it relevant and competitive with contemporaries. Upgrade or replace. Up or out. It’s not that hard.

Let’s look at some weapon systems that we could use to replace the harpoon. Two come to mind. One is the Brahmos, a joint Russian-indian antiship missile system. It’s launchable from surface ships, aircraft, trucks, and submarines. It has an operational range of 300-500 km. Even if we take the low end, that’s more than twice the quoted range of the Harpoon (“more than 124 km”). Oh, and it can go faster than Mach 2.8 terminally. Pretty awesome missile. It is, however, rather heavy at 2,500 kg for the air-launched version and 3,000 kg for the other versions. The Harpoon weighs a svelte 691 kg. So the Brahmos isn’t a perfect replacement; there are ships that we might want to give antiship capability to that can’t fit the big Russo-Indian missile. And Fishbreath will surely start complaining if I only choose a Russian system as a Harpoon replacement, and get upset if I demand bigger ships. Fishbreath likes his wee ships, you see.

An even better Harpoon replacement on a one-for-one basis is the Kongsberg Naval Strike Missile (NSM to you acronym-loving cool kids). The NSM is lighter than Harpoon at 410 kg. It’s range of 185 km is better than Harpoon (at least as far as quoted range goes). It’s got GPS integration. There’s a version that fits in the internal bays of our F-35s, which gets even more range (about 290 km or so). Most importantly, it’s stealthy. So the enemy will have less warning to react to it. It’s also cleared for a bunch of aircraft, ships, and land based vehicles already. Big gain right here as far as stealth goes, since the Russians have finally wised up and mounted CIWS on their ships. This is important, as NATO ships don’t usually carry enough Harpoons to overwhelm point defense systems.

There are a couple of experimental weapon systems of note that might be worth pursuing, namely the Anglo-French Perseus and Lockheed Martin’s LRASM (an antiship variant of the AGM-158 JASSM-ER). Both of these are stealthy, have good range, and are vertical launch capable. I prefer the LRASM a bit more since it’s based on an existing missile platform. Neither is available yet, but we’re content to get some NSMs now and wait for the fancy new developments from MEADS and LockMart for VLS tubes or longer range aerial strike missions.

Oh, and if we needed VLS integration to give our DDGs a big punch, or needed a lot more range than NSM, we could always go buy some BGM-109Bs again. Tons of range, fits in a VLS Tube. Another good choice while you wait for the fancy new stuff, and you can at least fit enough of them on a DDG to have a decent chance of overwhelming the air defenses of an opposing battlegroup.

I’m sure one last objection is coming from some of you. “But wait, Parvusimperator!” I hear you say. “What if I believe that I control the sea, and don’t really care about antiship missiles.” Well then. First, I would tell you that you’re an idiot. Even during the height of the British Empire, they maintained their position by having a navy stronger than the next two navies put together. You maintain your dominance by being able to crush all opposition, not by taking it for granted and going through some stupid hippie draw-down. But if you really didn’t care, no antiship missiles is lighter and cheaper than a battery of old crappy ones. Though, again, this is stupid. Antiship missiles are good.

Pistol Project Plan: Rock the Glock

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I’m a Glock guy. The first handgun I ever got, after getting a stupidly-hard to get NY State pistol permit was a Glock 19 Gen4. And I love it. Since then, I’ve gotten a bunch of other Glocks. I’ve got a Glock 17 Gen4, and I wanted to make this my latest project gun. First, let’s talk a little Glock history, and why I like them so much.

Gaston Glock designed his pistol to meet the needs of the Austrian Army for a new service handgun to replace the Walther P38. Gaston brought in a number of pistol experts to help him with his design; he was not a pistolsmith by training but brought extensive experience in advanced synthetic polymers, which would go into the construction of the pistol. The fancy glass-reinforced plastics used in the frame of the Glock pistol helped drive costs down, and since there are only four small points of metal-on-metal contact between the slide and the frame, Glocks don’t require much lube. Gaston also introduced ferritic nitrocarburizing as an anticorrosion treatment. The result was a pistol whose reliability and durability would become legend. The Glock 17 (so called because it was the seventeenth design), beat out the HK P7M8, HK P7M13, HK P9S, SiG-Sauer P220, SiG-Sauer P226, Beretta 92SF-B, an updated FN Hi-Power, and the Steyr GB. The Glock 17 was also accepted into Norwegian and Sweedish service shortly after winning the Austrian competition. The US DoD was even interested in trialing the pistol in their competition, but the DoD requirements would have meant retooling production in a short timeframe, so Glock declined.

So that’s why everyone loves the Berreta 92, right? The US Army called that gun the M9, and it became the most popular 9mm semiautomatic in Ameri–oh, wait. No, it didn’t. How did Glock do it? Once they had a whole bunch of NATO member military contracts in the bag, they went after the American law enforcement market with gusto. And their timing couldn’t be better. See, it was the 80s, and it was starting to dawn on the police forces of America that six rounds of .38 in a wheelgun and another six in a speedloader in your pocket wasn’t quite enough firepower1. Officers were looking to trade up, and Glock was ready with a super reliable pistol that was tolerant of neglect and could be made way cheaper than the steel-framed competition. Plus, Glock (possibly to overcome the language barrier or something), set up a pretty savvy marketing department, sending plenty of friendly reps to departments. Many of their reps were former police officers, and they brought tons of new pistols to try out on the range, along with plenty of swag. They offered low cost guns and top dollar for trades to appease the accountants, and were easy to get in touch with. So they captured market share in a big way. Currently, something like 65% of US Law Enforcement uses Glocks, including the FBI. Glock pistols are also super popular among the competitive shooter crowd, being the most popular brand by far at USPSA matches.

Glock currently makes pistols in about any reasonable pistol caliber you could want, and a couple oddball ones like 10mm Auto, and they’ve updated their pistols to bring new features to the consumer. Their current models are the Gen4 line, and it brings a bunch of notable improvements. Let’s take a look, and I’ll compare the Glocks to my M&Ps where appropriate. The Gen4s have backstraps now, with two different sizes (medium and large, “small” is accomplished sans backstrap), and they also have two backstraps with a beavertail, in case you get slidebite. Or you may just find those suit you better. Some people (including Fishbreath) aren’t really a fan of Glock’s grip angle. I personally don’t really care, though I’ve actually found myself getting back on target faster with Glocks when compared to other polymer framed handguns, so maybe it helps me keep muscle tension or something. In any case, you can change it now. The backstraps aren’t quite as good at changing the gun size as the M&P ones are, as they do nothing about the girth of the grip. This is not a problem for me, as I have large hands (I use the ‘large’ size backstraps). Others may find this an issue.

The Gen4 Glocks also have introduced a new texture on the grip. It’s much more aggressive than the old texture, or than the texture on the M&P grip, and I find this a significant win for the Glock. I like grippy, aggressively textured guns, and Glocks currently oblige me. If I wanted, I could have the grip stippled, but the current Gen4 texture serves me fine. It’s also not so aggressive that it will tear your hands apart after a long day of shooting.

Glock sights are, frankly, awful. They’re the white-dot-in-a-U design, which I guess is popular in Europe. I do not like them. They are cheap, and are bad enough to make some kind of sight replacement almost a requirement. This might almost be a service to the consumer, as there are many far better sight options out there. In this case, I’ll be getting my slide milled for an RMR, because red dots are awesome, and my M&P proved how good the setup was. If I wanted something else, I could get it for a Glock.

Ubiquity is something that’s great about Glocks. Anything you want for them, you can get for them. Holsters and sights and other accessories come to Glock first, because they’re so common. And Glock magazines, being made of metal-lined plastic, are stupid cheap, and easy to find on sale. More mags is always good, because magazines are a disposable commodity item. Mags wear out. Stock up.

While Glock beats out the M&P in terms of ubiquity, the M&P still takes second place, and is by no means bad (Seriously, compare prices of M&P40 mags with those for, say, a PX4). However, the Glock soundly beats the M&P on the stock trigger front. The M&P stock trigger, as I’ve mentioned, is a mushy mess. The Glock trigger is perfectly reasonable, especially considering that it has to be safe. There’s takeup, which is decently smooth. There’s some mush here, but it’s not altogether bad. Break is somewhere between the crisp and rolling variety. Finally, the reset is crisp and offers both audible and tactile feedback. The Glock trigger is not as good as a 1911 trigger, full stop. On the other hand, it doesn’t have a manual safety like a 1911, and it’s a lot cheaper than any actually worthwhile 1911. Technically, it’s a very light double action only trigger, that’s about two-thirds of the way precocked. Some trigger weight and resistance comes from the fact that you’re still doing a little bit of the cocking work on the striker with your trigger pull. Despite the downsides, the Glock trigger is firmly in the ‘good enough’ camp, and is more or less the standard for comparison.

There are a ton of fancy light competition triggers out there, as well as some parts to make the pull heavier if you want it to feel like an old school double-action only revolver (like the NYPD). I don’t much like making my triggers worse, and I shoot the stock one fine. Since I like to carry most of my Glocks, I won’t switch to a lighter trigger. The stock one is safe. I may try one of the fancy competition kits on my Glock 34 though.

On the M&P, I ended up swapping out the mag release for an extended one. The Glock Gen4 comes with an extended magazine release which is about perfect. It’s long enough to be easily pushed without switching your grip, but short enough that you won’t accidentally trip it when it’s in the holster. It’s a good compromise between a giant competition button and the tiny things that usually come on handguns. I see no reason to change it.

The Glock slide stop is a touch smaller than the one on the M&P. It is not ambidextrous, which isn’t as nice. Not shooting lefty most of the time, I don’t care. And I can always trip it with my trigger finger or slingshot the slide if I’m shooting weak-side. I will say that despite the minor-looking change on the factory “extended” slide stop that comes on the Glock 34 (really, it’s more of a reshaping than anything else), it’s actually a big improvement over the stock one for manipulations. I’ll probably get that upgrade for the rest of my Glocks.

Okay, I know you’re dying to know: which do I like more? That’s tough, but I think the Glock wins out overall. The stock trigger is better, even after applying the upgrade kit to the M&P. There are a lot more possible trigger upgrades for the Glocks, even though that’s not really my thing. Plus, I like the grippier frame better.

1. See: the 1980 Norco shootout and the 1986 Miami shootout, which I’ll probably do a write-up of someday.

Parvusimperator reviews The Bureau Gun

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It’s quite possibly the most tested 1911 ever. It’s certainly one of the most sought after ones. And, it’s even a bit of issued kit for the FBI’s legendary Hostage Rescue Team, 87 years after it was originally designed. It defies classification: it’s handmade by the Springfield Armory Custom Shop’s smiths, but comes with a very specific list of features. Want different ones? Then it’s not a Professional, and doesn’t get the cool serial number prefix. Or the knowledge that this pistol is built to pass one of the most ludicrous challenges ever presented to a modern handgun.

Background: The Challenge
When the HRT went looking for a sidearm, they put a ridiculous set of requirements in the RFP. They asked for a Pistol, Caliber .45, Model 1911. They wanted a 4.5 lb trigger pull (originally 5-6.5, later revised down). They wanted a warranty for 50,000 rounds. They demanded that the pistol be capable of firing three consecutive ten-shot groups from a Ransom rest no larger than 1.5 inches at 25 yards using the FBI’s .45 round of choice, Remington Golden Saber. The pistol then had to be fired for 20,000 rounds and undergo a reduction of not more than 15%. The pistol could not have a stoppage in 2,500 rounds. Only one manufacturer could make this happen–the Springfield Armory Custom Shop.

The Pistol
So what are the other features the FBI got in it’s pistol sans pareil? A classy matte black finish. A GI-type guide rod, none of that silly full length stuff. A skeletonized, commander-style hammer, made from hard, tool-steel. A skeletonized trigger. 20 lpi checkering on the front- and backstrap. A 5″ match grade barrel. An 18.5 lb. recoil spring. And the sort of supertight hand fitting that would make Les Baer proud. Also, the expected Novak three-dot tritium night sights.

Picking up the pistol, the first thing one notices is the 20 lpi checkering. It is sharp. It does not let go. You grip the gun, and she grips you right back. Some might not like this. Some might say they don’t need a pistol that may as well have a barbed grip. Those people are not me. I like a very aggressive texture on my grips, but if you prefer your hands not be heavily callused, you may wish to use gloves. The beavertail grip safety works as intended, and I haven’t been able to get it to not engage with any sort of weird, half-assed grip that I’ve tried. The thumb safety goes on and off crisply, and is small. Small so you won’t bump it accidentally. Small so it won’t dig into your side when you carry the gun. I’m fine with this.

The trigger. Oh, the trigger. This was made for insufferable trigger snobs like me. This is why people say that the 1911 is ‘God’s gift to gunnies’. It is so wonderful. It has the tiniest bit of takeup, and then a crisp break. Insert metaphors about breaking a glass rod here. It’s fantastic–and this from a guy who’s spent many hours with the finely-tuned hair-trigger of an olympic-grade air pistol. Unlike that, this pistol does not have a hair trigger. It will not go off if you brush your finger on it. But it will go off with just a little bit of pressure, so don’t be thinking about shooting until you want to be shooting.

Fit and Finish
Tight. Really tight. Between a lockup tighter than a bank vault and that 18.5 pound recoil spring, the first time racking the slide will make you question your manhood. It’s okay. Grunt. Curse. Breathe. You’ll get it. And no, you’re not getting the Pro apart without the use of that bushing wrench. That’s why they gave you one. It’ll loosen up some with use. It’s okay. That’s the point. It’s supposed to be like that. Go run your new gun. Your hands will thank you, and you’ll enjoy it.

The Black-T finish on the gun is classy. It’s subtle. It’s not inherently gorgeous like the carbonic blue on my old Model 29, but it’s very nice. It doesn’t really have imperfections, just a smooth matte finish that is designed to take some abuse. So what are we waiting for, let’s go shoot it!

Shooting the Professional
A crisp 4 pound trigger on gun that weighs somewhat north of two pounds loaded? Yeah, this gun makes you look good. This gun makes you look like you know what you’re doing, even if you suck. It’s all steel construction means that it soaks up recoil from the big, beefy .45 rounds. And one of the few benefits of the single stack design is that it fits everybody’s hands. And that trigger makes you want to keep shooting. It does however expect and demand that you have good trigger control. Try to live up to the Professional rollmark on the slide. Breathe. Fundamentals. It will magnify any errors you have in your technique, and put them on display for all to see. And you’ll come to appreciate that 20 lpi checkering, since it means the gun goes absolutely nowhere, despite firing big .45 rounds downrange. Before long, you’ll wish the magazines held more.

The Professional comes with six magazines, made by Metalform. 1911s being what they are, there are many different magazine designs out there for them. They only hold seven rounds, because seven round 1911 magazines are more reliable than the alternatives in general. This is as good a time as any to bring up a few annoyances of modern 1911s. Many different magazine variations means you need to find the one(s) your gun likes. And you need to keep an eye on them, because they do wear out. Being steel framed, 1911s run best with lubrication.

At this price point, those are about all the annoyances that there are. The price sucks, but if ever you got what you paid for, this is it. It ran great from the moment it left the box. The Professional is a joy to shoot.

Parvusimperator reviews the Det. Harry Callahan Special

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As mentioned elsewhere, my first gun was a Glock 19 Gen4. When I went back to the gun store to pick it up after completing the necessary paperwork to appease the fascists, I saw the clerk checking out something that had been brought in and sold. An old Smith & Wesson revolver. A famous one. A Model 29, complete with original wooden box, original papers, and a basketweave, thumb-break, police-type holster. Probably had given some police officer loyal service for many a year. Whoever it was, he had good taste. I have a weakness for iconic weapons, and this one is near the top of that list. Plus it’s got some police history (and I like old police guns). Most importantly, it’s absolutely gorgeous. I held it, felt the weight, and spoke those famous words:

“I know what you’re thinking, punk. Did he fire six shots, or only five? Well, to tell you the truth, in all this excitement, I kinda lost track myself. But being this is a .44 magnum, the most powerful handgun in the world, and would blow your head clean off, you gotta ask yourself one question: ‘do I feel lucky?’ Well, do ya, punk?

Then I put money down on it. Couldn’t resist. It would be mine. Evildoers beware!

I know I felt lucky to find this one. According to the serial, and some obsessive research, it was made around 1976 or so. It’s a three-screw frame, like most post-1960 Smith & Wessons. It was made long before S&W made their stupid pact with Satan–er, the Clinton Administration, so the frame doesn’t have a dumb lock that will break and render the gun unusable. Also, those frame locks are hideous. My Model 29 has a proper pinned an recessed barrel, which is another nice old feature that they did away with. It looks good, and its preferred by collectors. It was, of course, removed by Smith and Wesson as a cost cutting measure in 1982. Most importantly though, my Model 29 is absolutely gorgeous, primarily due to the legendary Carbonia bluing.

Carbonia bluing is the name for a process used by Smith and Wesson (and only Smith and Wesson) on their non-budget revolvers prior to 1978. It was a complicated and labor intensive process requiring careful heat control and polishing. It was based on an oil mixture from the American Gas Furnace Company, who sent Smith & Wesson the oil as a base, and S&W later added a whole bunch of other stuff to make it work. The story goes that there was only one guy at Smith & Wesson who knew the formula, and he kept it written in a notebook. When he died, his widow wanted $50,000 for it. By this point, Smith and Wesson had changed their bluing method to something less labor intensive, so they declined. She destroyed the notebook shortly afterwards. Now, American Gas Furnace Co. will happily provide you with an ingredient list if you ask, but the proportions aren’t on there. They don’t make the oil needed for the base anymore either. Several other ingredients are now discontinued, because they’re awfully carcinogenic. Oh, and one of them’s sperm whale oil–good luck getting that. And then you’d have to mess around until you got the process right. It might just be worth it though, because the Carbonia treatment gives a blue-black color that will have different color highlights as the light hits it. I might describe it as vaguely oil-like, but I’m no artist, so the technical term is lost on me.

Now that we’ve established the gun’s pedigree and gorgeous looks, you’re probably wondering how it handles. It’s heavy. It’s got a six inch barrel, wooden grips, and is all steel. It points reasonably well in the hand, but really needs two to be held comfortably. Once you fire the .44 magnum loads, however, you will appreciate every ounce of weight that it has. The trigger is a revolver trigger, but it’s an old, reasonably well used revolver trigger. So it’s been polished the slow and expensive way: by being fired a lot. Firing double action is heavy, of course, because you have to cock that hammer and rotate the cylinder. It is a textbook rolling break, and once you’ve fired it a few times you can stage it and get some wonderful results. Single action is a perfect glass-rod break. In fact, it might almost be too perfect. It’s very light, and there’s no takeup, so pressure will make it go with little warning that it is about to go. In any case, the trigger is wonderful in either mode.

Interestingly, I’ve left this gun completely stock. It has the sights that came on it: the front blade has a red plastic insert for high visibility, and the rear sight is adjustable with a white U-notch. Not that I could really do much about the sights without sending them off to a smith. The grips are the wooden ones that came with it. I could get something else, but somehow, that just doesn’t seem right. Maybe a set of vintage Pachmayr grips–I’ve heard those are better than the new ones. Still, somehow I don’t really want to mess with it–this is the Dirty Harry gun. It’s iconic the way it is.

No, it’s not the most powerful handgun in the world anymore. I don’t care. It’s a blast to shoot.

Borgundy Chooses A Carbine

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Here’s another challenge I tossed Fishbreath. It’s also a chance for me to wade into a bunch of classic internet arguments. First, we’ll deal with the old elephant in the room: the M4. The M4 gets an advantage over the competition by being based on an old (good) design, so the research and development costs are long since paid off. The Stoner-type operating system (colloquially known as “direct impingement”, even though the back of the bolt is technically a piston riding inside the bolt carrier assembly), means that it’s lighter than its competitors with similar barrels. Finally, Colt and the US Army have been quietly rolling improvements into the gun to improve reliability. Current mean rounds between stoppages is currently 1 in 6,000, which is phenomenal. The AR-15 series has the ergonomics that everyone loves to crib from, with the super-fast reloading magazines that drop free and a last-round bolt hold open. Nothing has a simpler or faster reload process than AR-15s, as evidenced by their competition popularity. The aluminum quadrail handguards and barrel nut serve as a heatsink, pulling heat away from the barrel and increasing the length of time to cookoff. But it would be really, really boring for me to just take an M4 and call it a day, so I decided to restrict myself to only the stock version available from Colt Defense, without all those fancy aftermarket gubbins. And also a legislature that wants a new, cool carbine. So, glossing over the M4, on to the new stuff!

We could go with a bullpup, but bullpups suck. The concept is to get a longer barrel in a shorter package for those obsessed with urban warfare. And shorter is better, but let’s remember that everyone’s classic idea of a room clearing gun is a Remington 870 with an 18″ barrel, and that’s the same length as an M16 overall, and longer than an M4. For vehicle ops, the shorter length is nice, but there were no complaints from using full-length M16A2 rifles in Desert Storm. Overall length is not the most important firearm characteristic. And we have to pay a significant price by going with a bullpup configuration. First, because the trigger is fundamentally detached from the hammer/striker, we’re introducing linkages, and thus a sucky trigger. This negatively impacts the accuracy of our soldiers. We can’t have a collapsible stock without sacrificing the length advantage, so we can’t adjust length of pull for body armor or different size soldiers. While most modern bullpups have switchable ejection, so left handers don’t have to eat a steady diet of brass, this isn’t really something to be done in the field, so soldiers can’t choose which side of cover to expose themselves over (Well, unless they want to expose most of their torso, and that’s silly). Modern bullpups tend to lack rail estate, and don’t have easily swappable handguards, so they’re harder to accessorize with lasers, lights, thermal scopes, and all the other accoutrements of battle. Finally, reloading is awkward for a soldier wearing modern body armor (i.e. with hard plates) and load bearing equipment. The SAS basically teach soldiers to move the back end of the rifle from the shoulder to the middle of the chest in front of the stuff that the soldier is wearing in order to be able to manipulate the magazines effectively. It’s interesting to note that for the vast majority of countries who issue bullpups generally have their hardcore tier-one special forces operators use a conventionally-configured rifle. And it’s nearly always an M4. When it’s not it’s something like the HK416, which is 95% M4. So, really, why bother? There are more important things than having the shortest carbine. But in case you don’t believe me, let’s look at some specific bullpups and why they suck.

The AUG sucks
The Steyr Aug was one of the first bullpups, and it looks really cool. It has a quick-change barrel, but who cares? Soldiers won’t carry a bunch of extras in case they shoot one out playing Rambo. And they’re not going to swap barrels before a mission. So, cool but useless feature, check. It’s got a really crappy trigger where a partial pull shoots a single shot, and pulling it all the way back shoots fully automatic. Possibly one of the most bone-headed trigger ideas of all time. Are the Austrians too good for a normal fire mode selector? Eventually the Irish got fed up with the stupid, and added a little locking catch to the trigger to function as a fire mode selector. It probably makes the trigger even worse. It uses it’s own proprietary magazines, not the M4 magazines that everyone and their uncle makes, and that many companies in America have worked to improve. They’ve finally figured out in the A3 version that last round bolt hold open is good, and that people might want something that isn’t the tiny 1.5x scope that came on the original. Good for them, but good luck mounting anything more than another optic on that small unit. God forbid you want to add some night vision or a laser or a light. Oh, and you have to do some serious modifying to make it work with an underbarrel grenade launcher like the M203, since most quick-change barrel assemblies have a built-in vertical foregrip. But don’t worry, it shoots rifle grenades. Which is great if it’s the 1920s and you’re French, but the rest of the planet has moved on. Oh, and it was kicked out of the Norwegian service rifle competition early, which probably means reliability sucks.

The F2000 sucks
The FN F2000 is the one bullpup where you can switch sides at will thanks to the forward ejection system. On balance this is a good thing, though it’s going to piss off every range safety officer in the world. And it’s going to make clearing a jam a new special level of hell, since you have to start opening little ports to be able to get at anything. It doesn’t have a last round bolt hold open, which is lame. Again, there’s minimal space for accessories, so you’ll want to contract for some adapters, or fight like it’s 1983 all over again. It comes with a pretty lame 1.6x sight by an unknown manufacturer, but at least there’s a rail under that. I will give points to FN for doing a good job with a grenade launcher attachment. They have a reputation for having poor reliability and being maintenance intensive–maybe because you need trapdoors to get to the operating parts, maybe because its ambidextrous design is too clever and ends up being a magnet for things that cause stoppages. But hey, it’s been adopted by Slovenia, so there’s one not-so-major military who thinks it’s ok. Oh, and it’s Gadaffi approved. At least the other bullpups here have been adopted by a bunch of actual militaries.

The Tavor Sucks
The Tavor is probably the best bullpup around right now. That said, the trigger on it is really horrible, even by military standards. It has feed issues when trying to run it with Pmags. I have no idea how well the design deals with heat from a bunch of shooting–probably badly, since it looks like it’s just going to trap most of it. There’s room for a red dot, but accessory placement options are pretty limited when compared to more conventional designs. Accuracy testing has produced mixed results, with many of the more reliable sources giving poor accuracy under otherwise good conditions. And it still suffers from all those inherent bullpuppy drawbacks. If you wanted a bullpup, this is the one to get, but we don’t.

That leaves conventional carbines. By similar reasoning as in our pistol post, the ARX-160 is out because no one else has bought one yet, and it also has a bunch of extra complications internally (switchable ejection? Really? Just use a brass deflector). That leaves the HK416 and the FN SCAR 16. Another classic internet argument, yay. First thing we notice is that the SCAR is lighter than the 416 by a lot. And it has a cool stock that collapses and folds, instead of just collapses. All that is good, but a good chunk of the weight of the 416 comes from a heavy barrel profile, large steel barrel nut, and large aluminum quadrail handguard. This all works to provide a big heatsink that means that the HK416 can deal with waste heat better than other carbines. When the USMC wanted an automatic rifle for more sustained fire than a regular M4, HK basically engraved USMC on the side of a regular 416 and called it good–and won. They didn’t need any fancy closed bolt/open bolt hybrid operation system; the HK416 met all of the rounds-until-cookoff standards that the Marines wanted as originally designed. Further, the extra area of the rail means that there’s more room for a soldier’s hands, plus the increasing number of accessories that the mission might call for. The other big advantage is that the HK416 is issued more widely, so more bugs have been worked out. It’s the general issue service rifle of Norway, and is the USMC’s new automatic rifle. So we too will go with the HK416.

Borgundy Sidearms

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Not wanting to throw a challenge to Fishbreath that I could not do myself, I think I’ll pick a sidearm for Borgundy. Like the US Marines, we tend to issue anyone who might see some combat somewhere a carbine. Yes, even officers. But it would be a colossal copout to write “see carbine post”, and there are still some needs for pistols, so we should pick one of those too. First, caliber. This part is easy: 9mm Parabellum. Frankly, pistol calibers suck at combat (which is why we issue so many carbines), and the only reason you fight with a pistol is because you don’t have anything better at hand. Once we accept that, 9mm is about the smallest acceptable round in terms of ‘pistol stopping power’, and going bigger doesn’t get us much more in stopping power (since .45 ACP is still a sucky pistol cartridge, not a manly rifle cartridge). Choosing the smallest acceptable round gives us more rounds per mag and lower recoil, which is important since most military guys don’t shoot their handguns all that much. So they get the most chances to hit, and the lower recoil makes follow-ups faster.

That entirely too predictable choice out of the way, we come to the decision of which pistol to pick. There are many to choose from, so let’s run down what we need in a pistol. We want a reliable pistol, that’s also reasonably priced (come on, it’s a pistol…there are better things to blow cash on) and accurate. Unfortunately, this doesn’t help us very much. There are tons of pistols that meet these criteria. We’ll go further by requiring it to have been already adopted by another major military, since we don’t want to be a testing ground for such unimportant things. We do this because pistols aren’t worth losing sleep over, but it still doesn’t help us very much.

We still have several excellent pistols in the running, including the Beretta 92, the SiG P226, the Glock 17, the HK USP, the Browning Hi Power, and the CZ 75. Now we come down to pedigree and shooter’s preference. Shooter’s1 preference being what it is, the Hi Power gets tossed out for having a stupid magazine disconnect. It’s also the oldest of the bunch. The Beretta 92 is the next out, since I don’t like the combination safety/decocker. Why would I both add a step to my draw stroke that I might forget and have a long, heavy double-action pull? No thanks. We’ll next toss the SiG since I’m really not a fan of double action triggers on semiautomatics. On revolvers, I see the point, on semiautomatics I do not. I don’t like the double action/single action transition. Both the USP and CZ can be carried cocked-and-locked, which I like. Gives me that consistent trigger. So we have gotten it down to three on purely preference grounds. The CZ has a somewhat less favorable reputation for reliability than the HK and the Glock according to the best sources I can find, so it’s out. The HK and Glock are both hard to beat in that regard. HK vs. Glock is a classic internet argument, but for our purposes the decision is simple: Glock is cheaper, and in all other characteristics, the guns are comparable, so we’ll go with Glock. More specifically, that Glock 17.

Well, that was easy.

1.) Namely mine

Pistol Sights

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The most basic sights worth writing about are the classic patridge sights: black front sight post, black rear sight. No markings at all. If you’re doing bullseye shooting, these will work fine. If you don’t have good lighting conditions or if you’re going for speed, these leave much to be desired, usually. Note that we can get some better speed with these if the sight post is narrower than the notch, but this almost never happens. These are usually marketed to the bullseye crowd, so the post is kept as wide as the notch to maximize precision.

I should probably mention three-dot sights now. You know, three little white dots, it’s about the industry standard. I can’t stand them. I hate three-dot sights. I don’t like them at all. I don’t think “lining them up” is a very good decision, because there are a couple different ways to do it. Really, you have to line up the tops of the sights, but I don’t think this is very intuitive, unless you actually look to line up the post and notch, not the dots, and then what’s the point of the dots? I also don’t like that there’s nothing distinctive about the front sight here. Your focus should be on the front sight, even though it’s dot is smaller than the other two. There’s nothing to draw your eye forward, and maintaining that front sight focus is hard. Don’t help novice shooters, sight designers. Probably because nobody actually likes these sights, you can’t really get these customized with a smaller post at all. These are placeholders that you should rip off your pistol and replace at the earliest opportunity.

I should also cover XS big dot sights. I don’t like these either. They’re supposed to be super fast up close, which is almost certainly true. But there’s no precision. It’s a needless specialization–you can only make one kind of shot with these, and close in shots are where you can index off the frame if you need to, because close. Or, you could get crimson trace lasergrips (which I’ll discuss later) and have something even better in close, and still be able to have sights that work at range. Don’t get these.

Next, let’s talk about tritium. Lots of people think you should put tritium sights on your gun in case of a low-light encounter. I have two problems with this. First, the only body of statistics I have on CCW holders involved in gunfights indicates the vast majority of them occur in well-lit areas. And in well lit areas, tritium dots suck, since usually the rear sights catch light and are pretty bright and annoying. The front sight will catch light too, but it’s further away, and it will look smaller. So you’re focus is drawn to the wrong place. My other problem with tritiums is that, if I am fighting in poorly lit areas, I’m going to need a light. Preferably a weapon-mounted light, which is going to wash out the tritiums. The white light is to identify a target, but it will make the tritiums not help at all. And no, the light will not give your position away. Don’t be stupid. The light has an off switch. If you do want tritiums, I actually prefer three-dot tritiums to the weird two-dot ones out there. Three dot lets you get sights lined up in both dimensions. I also like subdued rear sights, preferably in amber, so that in poor illumination the brightest dot will be the front sight. I also only like a white outline on the front sight, so in better illumination the rear dots won’t be lit up too much. If your tritiums aren’t set up this way, you can give it a try by running a sharpie over the rear sights a few times.

What I really like in iron sights are a narrow fiber optic front and a plain black rear with a wide notch. It gives me a nice balance of speed and precision, and my eye is drawn to where it should be. In well lit conditions, like the range, or outdoors or the well lit areas that most CCW gunfights have happened in, fiber optics work great. Bright front sight is easy to see and easy to keep focus on. In low light, it’s much less helpful, but if you’re using a light, poorly illuminated fiber optic sights look a lot like washed-out tritium sights. I don’t like any fiber optics or dots on the rear, because that’s my reference. I don’t want it complicated. I don’t want anything competing with the front sight for focus.

Let’s talk technology. First, crimson trace laser grips. I really like these, mostly because of the instinctive activation. I grab the gun, the laser is on. No switches to forget about. Nothing to fumble with. Lasers aren’t very good in bright light, at long range. But that’s okay. They compliment traditional irons, because they excel where other irons suck, in low light, in unusual positions. Lasers are way better than tritium in low light. And if you have to engage from a weird shooting position, lasers are there to help. Works great if you want to cheat a little on the Tueller drill. Oh, and if you think lasers will give your position away, you’re stupid. Just like lights, lasers have this fancy new thing called an off switch. Also, for the CCW users, you’d have to defend your use of force as justified, which almost certainly involves being threatened, which probably means that the bad guy knows that you’re there already.

Finally, we come to my favorite overall choice: the mini red dot (on the slide). I won’t lie, these are stupid expensive, especially if you do it right and get your slide milled for a particular red dot. But the red dot is great. No sight alignment to worry about. No focus to worry about: you focus on the target, bring up the dot and just let it float in your vision. It’s great at range, and it won’t obscure your target. For 95% of shooters, it’s easier to run a red dot fast and well than any kind of iron sights. Those top shooters, the guys who can visually track the rear sight through recoil, might see a loss of speed, even after practicing. For everyone else, I think the mini red dot is by far the superior choice.

I’ll probably write up my red-dotted S&W M&P 40 sometime soon.

On tafl: game tree search optimizations

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As you’ll recall from the tafl piece about complexity, tafl has a high branching factor compared to, say, chess1. That means that a tafl game tree is broad: it has a lot of nodes relative to its depth. Since searching deep into a broad tree is difficult, getting good lookahead out of a tafl engine is going to be difficult. And, to be clear on where this post is going, it started off being extremely difficult.

Before I get there, though, I want to talk about the state of the art in chess AI as of now, or at least a few years ago. (Recent sources are probably easy to find if I were to look in the right places, but I forgot I still have a .edu email address with which I can probably sneak into a bunch of online article repositories.) Chess engines, today, on a moderately powerful desktop computer, are able to generate about four million game states per second. They also have highly advanced pruning2: not only the standard sort I’ll go into in a later post, but also a more qualitative sort, discarding moves that pass the plausibility test but fail the usefulness test.

Four million states per second is an extremely high bar to hit. Chess engines have been in development since the dawn of digital computing, just about, and fifty to sixty years of optimization really shows3. I told myself I’d be happy with somewhere between ten and twenty-five percent of chess’s state of the art.

How far did I have to go? Well, I coded up my state explorer, put a bit of benchmarking code in, and set it exploring three ply deep in brandub. It chugged along for a while, and then, almost forty seconds later, finished. The number? 1,000 states per second, which comes to between four hundred and one thousand times too slow.

Ouch.

I quickly discovered a few obvious things I could fix. First, I was doing an expensive operation (getting the allowable moves for a piece) for every piece on each side, to check if either side had no allowable moves remaining. I replaced that with a short-circuit check that returns true as soon as it discovers any allowable move for either side, which is a much quicker proposition. Second, I was checking for edge forts at the end of every turn, whether or not the game allowed for edge forts. I put a stop to that. Third, I was checking for edge forts in a vastly more expensive way than I needed to, to allow for a situation that does not occur in any known tafl variant4.

Confidently, I ran the benchmark again: 4,000 states per second.

Well, I’d been hoping for more than that.

I did a little reading, and decided some of my problem was with the programming language I’d selected. My language of choice for most of my side projects is a scripting language called Groovy. It’s Java’s little brother, sort of; it provides a bunch of shortcuts Java does not for displaying things to the terminal, handling user inputs, playing around with files, and iterating over sets of objects. I suspected from the start that Groovy might cause me headaches, and profiling suggested that was correct—my code was spending most of its execution time in Groovy’s internals. Rewriting it in Java was quick, as such things go, and with that squared away, and me optimistic as to my chances, I set up another benchmark.

15,000 states per second.

Three times faster is great, but I still had a few orders of magnitude to go.

I decided that the board representation I had started with was clever, but inefficient. My profiler suggested I was using literally tens of millions of objects: each space was a first-class object, in the first reckoning. This would not do; objects in Java may be small, and instantiating them may be fast, but there’s a limit to what a Java virtual machine can be expected to put up with. I removed the class of object which represented spaces, and set about rewriting the code to reference an array of small integers to represent a board.

Moving to an integer representation meant that I had an opportunity to come up with an encoding I can eventually use to rid myself of helper objects altogether. (As I write this, I’m still using a class of objects to represent taflmen—they’re inflated from the integer representation when needed, and compressed when the state is no longer active during a game tree search.) The first six bits of the integer are used for an ID number—each taflman-representation has a unique ID within its side. Six bits lets me define up to 127 taflmen per side, which is sufficient for every known variant, and leaves some room for busier alea evangelii variants, if desired. The next three bits define the piece’s type. I’m aware of five potential types of taflman: a standard taflman, a knight or a commander from berserker, a mercenary (a defending piece which switches sides when captured, seen in one proposed alea evangelii variant), and a king. Finally, the next bit defines whether the piece is a besieger or a defender.

I was a little put out to realize that my efforts did not actually buy me very much—I was still at about 15,000 states per second.

My next task was to observe the behavior of my code, and find out where it was performing poorly. An unexpected but obvious optimization presented itself. When you run a Java program, it defaults to using a small amount of memory. You can provide command line switches to allow it to use a much larger amount of memory. Doing that, I found I was up to 50,000 states per second—that’s getting somewhere.

In fact, that’s what I’d call having gotten somewhere. 50,000 states per second is sufficient to play a game of brandub to a search depth of 3, without undue waiting. (It takes about 40,000 states explored to get to depth 3, and about 1.2 million to depth 4.) I whipped up a quick evaluation function (which I’ll describe in a subsequent post), hooked it up, and quickly found that it played only slightly more poorly than I do5.

With that heartening development, I also stumbled upon a happy fact. Java is, at first, an interpreted language, but it compiles sections of programs to faster, native code when it discovers that it runs into them a lot. After the computer took its first turn, I saw the benchmark report that it had explored 200,000 states per second. 200,000 states per second I can live with—my laptop is several years old and a laptop, and in testing, my desktop was about five times faster in an earlier version of the code. I intend to test it again soon, and see what a powerful machine can do with it.

I made one final optimization after that. Since the AI code used a thick representation of game states, it was extremely memory-hungry—brandub to depth 3 took over four gigabytes of memory, and other games were impossible altogether. I solved that one with two changes: first, I now represent the explored nodes of a tree as a list of moves required to reach each node from the root. Second, I trigger garbage collection manually.

Now, this may seem like a bad idea, to those of you with some Java development experience, but in this case, it’s called for. The default Java garbage collection scheme is two-leveled: objects just created go in a group called the Eden space. The Eden space contains objects whose longevity is not known, and which will therefore likely be quickly removed. If an object survives garbage collection in the Eden space, it moves into the Survivor space, where middle-longevity objects live. The Survivor space is touched less frequently by garbage collection. Finally, if an object lives in the Survivor space through a couple of garbage collections, it moves into the Tenured space, where it is troubled by garbage collections least frequently of all.

A lot of my objects end up in the Tenured generation—the objects which represent boards, particularly. They’re long-lived and durable, while almost every other object in the code comes and goes somewhat quickly. That means that Board objects, which are rather large, and which also contain references to other, shorter-lived objects, stay in memory more often than I’d like, and keep their sub-objects in memory, too. Triggering a garbage collection manually garbage collects everything, regardless of the space in which it lives, so the Board objects are cleaned up, freeing space. It does slow the code down somewhat: I get about 120,000 states per second on my laptop now, under ideal conditions.

Like I said, I can live with that. It’s not where I want it to be, but it’ll do for the time being. Coming up in the not-too-distant future: writing on evaluation function, although I have some research to do before I’m done with that.

1. Go starts out branchier than 11×11 tafl variants, obviously, since you can play a stone at any point on the board. Thinking in terms of smart opening moves, I suspect the order still goes go, 11×11 tafl, chess. Large (that is, 19×19) tafl variants probably branch more than go at almost every stage of the game; the board is the same size.
2. That is, trimming unproductive branches from the game tree before expending the effort to explore them.
3. Here’s one for you. Computer memory is organized into bytes: eight slots to hold either 0 or 1 (called ‘bits’). Some data types are eight bytes long, or 64 bits. The chess board is 64 spaces, so someone had the idea to represent chess boards in a single eight-byte long integer. You need a few of these bitboards to represent a whole chess game state, obviously: minimally, two to represent which side controls each space, and six to represent which kind of piece occupies each space. Even so, it’s very compact, and bitwise operations on 64 bits at a time are blazingly quick on today’s 64-bit CPUs.
Unfortunately, this does not generalize well to tafl; most of the boards we concern ourselves with are larger than 64 spaces.
4. Namely, allowing black, using Berserker-style pieces, to jump into a Copenhagen edge fort to break it.
5. This says a lot more about me than about the AI.

AAR: M&P40 Project

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This is a new one for me–I’m talking about the results of a project gun rather than the planning phase. So I’ll try to give you planning bits too, but they’ll almost certainly be hindsight tinted. I’ll also make this partially a review, but that’ll be hard to do because I do love to tinker, and this is hardly a stock pistol anymore.

I picked up a Smith & Wesson M&P40 for a few reasons. I had given them a shoot over at the Gander Mountain Expo, and rather enjoyed the experience. Plus, I wanted to try something a little different from the usual “Glock 9mm” that I had tended to shoot up to that point. I debated the M&P in 9mm, but those had some issues in the not too distant past. The M&P was designed first for the .40 S&W round though, and those hadn’t had problems. Plus, I always wanted to give the .40 S&W round a try, and what better platform to do it with?

The .40 S&W round is an interesting one. It occupies an intermediate position between 9mm and .45 ACP. You get more rounds in the mag than you would with a .45, but you give up a couple to a 9mm pistol. It can still fit in a 9mm frame though, so those of you with small hands won’t gripe as much about fit. Oh, and the .40 S&W is a hot round. The .40 S&W grew out of the 1980s dissatisfaction with .38s and 9mms from the FBI. Initially, the FBI went with the 10mm auto, but this required the same sort of big frame as a .45, and was a really hot round. Female shooters and the recoil averse weren’t very happy, so the FBI had ammo makers make them a lighter loaded 10mm auto. From there, someone realized they could shorten the case somewhat and fit it in the same frame as a 9mm, and thus the .40 was born. It’s a super popular round for law enforcement. Modern ballistics being what they are, 9mm hollow points have caught up, and now (joy of joys) you can get good hollow points in all major calibers that pass the FBI gelatin tests. 9mm has a small advantage in magazine capacity, and is a bit cheaper. But there’s nothing wrong with .40; it certainly won’t get smaller when it hits something. It maintains it’s energy edge, and some have called it ‘snappy’ or ‘hard recoiling’.

When Smith & Wesson decided to challenge Glock properly in the polymer-framed striker-fired pistol market, the resurrected one of their most storied brands: M&P. The original Military and Police, also known as the Model 10, was an extremely popular service revolver for police officers and various militaries, as well as being a popular pistol in the civilian market. It’s the most popular centerfire revolver of the 20th century, with some six million being made. There are a number of things to like about the current-production M&Ps from design and user standpoints, and I also have a couple gripes.

First, the good stuff. The M&P is wonderfully comfortable in the hand. The interchangeable backstraps are the most comfortable that I have played around with1, and they do a really good job of accommodating various hand sizes. The backstraps change both length and width of the grip, which is super helpful. The backstraps are held in place by a handy pin/tool thingy that is inserted into the bottom, behind the magwell. We’ll get to this later, but it’s pretty handy to always have a gunsmith manipulation tool with your pistol. The slide stop is ambidextrous, and it’s well positioned to be far enough back to be easily reached with your strong hand thumb, but not so far back that you might be tempted to rest your thumb on it and prevent the slide from locking back on an empty mag. It’s also not so far forward that you might rest your support hand thumb on it and do the same thing. Sizewize, it’s big enough to be easy to manipulate, but small enough that you don’t hit it accidentally. It’s a really solid design. I’ve also noticed that it drops the slide automatically if I insert a full magazine with gusto. I’m not sure if this is a design feature, but I like it.

There are a whole bunch of minor things that I like too about the M&P. The slide cocking serrations are really good. They’re sort of a fish-scale design, and they’re quite grippy. I really like grippy. Plus, they look cool. Also, in the minor details that I like column is the dovetailed front sight. I much prefer front sight dovetails to the stake/screw method, especially when you put nice aftermarket sights on your pistol. Dovetails are the way to go. I also rather like the rotating takedown lever much more than the pull tabs of Glocks or HKs. It’s a really little thing, but hush, I still like it. One of the niftier little things is a small internal lever (that you can trip with that tool in the back of the grip) which is used to release the sear for disassembly so you don’t have to pull the trigger. Since plenty of accidental discharges occur on the disassembly phase from complacency, I sort of like this feature. Even though I tend to disassemble my M&Ps with a trigger press, because I’m lazy.

Safetywise, I got my M&P just like my Glocks: No external safety. Since they’re going for the law enforcement market though, Smith and Wesson is nice enough to let you choose what safeties you want. If you’re like me, and don’t like external safeties, you don’t have to get them. If you’re like Fishbreath, you can get them on your M&P, and they’re even frame mounted as God and John Moses Browning intended. If you’re mental, or an overly-paranoid police department, you can also opt for a magazine disconnect safety in addition to the external safety (or lack thereof). Fishbreath and I do agree (you’re shocked, I know) that magazine disconnects are stupid.

So the M&P feels good in the hand, and has a bunch of nifty features. What don’t I like? Well, two things. One is minor: the mag catch. Or more precisely, the bit of plastic behind the mag catch. It makes me reach a little more to get to it, and makes pressing it a little uncomfortable. It’s a really minor gripe, I know, but it bothers me. I’ve ordered up an extended mag release, and that’ll probably fix it. More troublesome is the trigger: it’s not very good. The stock trigger has a rather mushy takeup, a really hard wall to release the sear, and then a soft, weak reset. UGH. While I could send it off to a gunsmith, it’s much easier to buy an Apex trigger kit and put it in yourself. The end result is a trigger with more pretravel than a Glock, but a very respectable reset and a somewhat less obnoxiously wall-like break. The Glock trigger is still a trifle better, but that might be just because my test glock at hand has lots of rounds through it, polishing everything up inside the slow and fun way. Without the Apex kit, the M&P trigger is annoying. With it, it’s a pretty good polymer service pistol trigger. It’s nowhere near as good as my 1911, but it was a whole lot cheaper too. It does bother me that S&W can’t make their triggers suck less though, but it’s a simple fix away.

I should also point out a significant advantage of the M&P (and to an even greater extent: Glock): ubiquity. These pistols are everywhere. Finding parts, accessories, or a factory certified armorer is easy. Magazines are cheap. And new sights come to you first. Finding holsters is easy. It lets you pick what you want to experiment with, and run the gun the way you want to, rather than the way that you can find accessories to accommodate you.

So let’s go over the pistol. I’ve already mentioned that I put an Apex trigger kit in. Specifically, it’s the duty/carry kit. There’s also a competition kit available if you want a lighter trigger. Fringe benefit of installing this myself is that it really helped me get a good understanding how this pistol (and other, similar striker-fired pistols) work. It wasn’t a very hard install. I also am going to try out an extended mag release, see how that goes. I also sent the slide out for milling to install an RMR. Why RMR? Because it’s tough. It’s built right. The adjustment dials are in good places, and battery life is excellent. I had the milling done by Mark Housel of L&M precision, and he did a really great job. I also have suppressor-height Ameriglo iron sights mounted as backups. These are there in case the battery dies at a bad time, or Murphy and his law find a way to make a bother of themselves. They also help find the dot if my presentation isn’t good.

I’ve already discussed the mini red dot academically; now I’ll talk about what I’ve found. The red dot will make any issues in your draw and presentation painfully obvious. It’ll also wobble a bit, picking up on all those tiny little twitches. And, it slows you down initially, because you’ll often find yourself wondering, “where the hell did that stupid little dot go?” But after some practice, I found that it made me faster. It made me more accurate. It helps in dry fire, because it makes errors in your trigger press a lot harder to ignore and ‘cheat’ through. Oh, and if that’s not enough of an endorsement, I sent another slide to Mark to work his magic on.

1. I’ve heard HK and Walther’s newer designs are as comfortable as the M&P, if not more so, but I don’t have serious time on either, so I could not possibly comment. A PPQ of some flavor is probably the next pistol I get though, judging by all the rave reviews its trigger gets. So stay tuned.

Skypirates: lessons in zeppelin aircraft carrier design

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When I worldbuild, I put great importance on doing the background work, even background work which doesn’t feature in the foreground very often. So it is with zeppelins in the Skypirates world. Not only do we design them in the same modes and manners as real rigid airships, we’ve discovered that, to our surprise, they’re not quite as implausible as we thought.

Which isn’t to say that they aren’t implausible. We’re making a couple of assumptions rooted in our alternate history that are, well, unlikely. First: we assume that the limit on the size of airships was not one of 1920s and 1930s materials science, but rather one of insufficient ambition. Second: we suppose that engine technology in about 1925, owing to a few more years of the First World War to incubate, has reached levels not seen until ten or fifteen years later1. Third: we assume that large airships are much cheaper than they were in actuality, and that they’re much more common. Fourth: we assume a couple of highly-specific technological advances with respect to gas handling.

If you’re unfamiliar with airships, that last one might seem oddly specific, but it turns out to be critical. There are exactly two practical lifting gases2: hydrogen and helium. You may remember from high school science that hydrogen makes a tremendous *thump* as it blows up in the presence of flame. This doesn’t necessarily rule it out for zeppelins-of-war, but it does push it firmly into the realm of the sub-optimal. That leaves us with helium.

Helium is a pain. Its most notable characteristic3 is its mad delight in escaping every container you try to put it in, including Earth’s atmosphere. Its second most notable characteristic is its relative rarity. Because of its eagerness in leaving the planet once it’s free, there’s very little of it in the air, and it’s difficult to get out of the air. In the timeframe in which the Skypirates stories takes place, the United States historically controlled most of the world’s helium supply4, and, for political reasons, the Germans were unable to buy any for the Hindenburg. (And we all know how that turned out.)

Now, we also had another problem, not all that closely related, but ultimately in the same vein: aircraft-carrying zeppelins are heavy, and anything you put inside a zeppelin’s hull doesn’t just count against your total lift, it reduces it5. I’m going to introduce a term here, and I’m sure it’ll make airship engineers tear their hair out, but here we are: reserve displacement.

If you have a fixed amount of gas inside of a stretchable container, then reduce the pressure outside the container, the container will expand, and the pressure inside will drop. Although less air mass is displaced per unit volume, the container’s volume grows, and the container still makes lift. This effect explains why high-altitude weather balloons look tiny when they take off, and then get huge when they reach high altitudes. High-altitude weather balloons have high amounts of reserve displacement.

Rigid airships aren’t designed with lot of reserve displacement. Their gas cells start out almost fully inflated, for a very simple reason: over the course of a flight, airships get a lot lighter. Your choices are either to vent your lifting gas when you’re nearly to your destination, or rely on complicated ballast recovery systems to capture water vapor from your engine exhaust. One puts you at the mercy of the ground facilities at your destination6, and the other only works in the absence of heavy flight operations. Launching and recovering lots of planes is the same thing as dropping and taking on tens or hundreds of tons of ballast over the course of a few hours, and reality has no way to mitigate that.

So, we’re presented with three little plausibility concerns that get in the way of storytelling: zeppelins don’t have much room for gas cell expansion, limiting them to a narrow band of altitudes; realistic methods for landing require a loss of lifting gas unlikely to be available at your friendly neighborhood jungle ruin filling station; and air operations break all normal procedures for trimming and ballasting. We invented two pieces of retro-scientific fictional technology to gloss over those plausibility issues, both products of fictional Imperial German zeppelin pioneer Karl von Rubenstein.

The von Rubenstein cell is a specially-treated fabric gas cell with a fantastically7 useful characteristic: it is helium-impermeable (don’t ask me to explain it; I just said it’s fiction). von Rubenstein cells can be used as trim tanks, in a sense—if you limit a cell’s expansion, you can pump helium into it, and plain air into the others. The air-helium mix generates less lift per unit displacement, and the trim cell is holding more helium, but isn’t displacing any more air, and the lift goes down.

The von Rubenstein pump is what lets us move helium around so easily. Passing a mix of gases through its machinery yields helium as one output, and everything else as another. The air-helium mix inside a gas cell can easily be separated back into nearly-pure helium, thus raising the trim altitude again, and even atmospheric helium can be extracted, albeit slowly.

Combining the two, we have a model for airship operations. The secret is that modern zeppelins in the Skypirates world aren’t built with a lot of ballast. They’re built for a ceiling, with helium capacity and reserve displacement for that ceiling. In their untouched configuration, that’s their ‘trim altitude’—where they’ll end up, absent other concerns. To descend, or to land, or to launch aircraft, the crew pumps extra helium into the trim cells, and the zep’s lifting capacity goes down.

Practically speaking, there are a few inescapable limitations. For one, a zeppelin’s initial trim altitude—its pressure height, as the technical term goes—is inversely related to its lifting capacity. To leave room in the gas cells for high-altitude expansion, the gas cells must not be filled at sea level, and doing so leaves buoyancy on the table. To some degree, trim cells mitigate this—the excess can be pumped in and held at pressure, and eventually the reduced amount of helium in the lift cells will balance out the zeppelin’s weight, or either trim or lift cells will explode8. Between that and limited ballast, though, we have the ability to let our zeppelins cruise at a broad range of altitudes, which was our aim in the first place.

Another of those inescapable limitations comes from structural strength and weight. It strikes me as unlikely that zeppelins of the bulk we’re talking about could be built as lightly as we say the are. Assuming I’m wrong, we’re within about 10-15% of actual, possible zeppelin designs, in an ideal world, with our fantasy technologies. If I’m right, the figure is more like 25% or 30% off, I’d wager.

Even so. When I first went over the design rules parvusimperator found for zeppelins, I thought to myself, “This is awesome, but utterly impossible.” From ‘utterly impossible’ to ‘we just need to be about one-third lighter than aluminum actually is’? That’s progress.

Expect a few more posts on zeppelin design in the near future. For one, I’ve completed a first draft of a vaguely technical cutaway drawing of Inconstant, which may eventually show up on a mug, and I want to go over it some. For another, I mentioned the zeppelin construction rules, and I feel like I should provide those, too, pending parvusimperator’s approval.

1. This is not zeppelin-specific, but it does explain our extreme fuel efficiency.
2. Impractical lifting gases include water vapor, ammonia, methane, simple hot air, and (yes, I know it isn’t a gas) vacuum, all of which don’t work in large airships for various reasons.
3. Besides being lighter than air and making your voice funny when you inhale it, that is.
4. It comes from natural gas wells, mostly.
5. Airships work by displacing air with a lighter lifting gas. When you’re putting aluminum hangar plating or a library in the place of gas cells, you’re cutting into your displacement.
6. “Top me up! I need about five hundred thousand cubic meters!”
7. In the sense of fantasy, too.
8. This is bad.