Author Archives: parvusimperator

Soldiers’ Gadgets: Geissele High Speed Selector

The AR-15 selector is a pretty standard component. There are a few variations on the lever shape, some including an ambi part for lefties, but it’s worked the same way since the 1960s: Point the lever forward (“0 degrees”) for Safe, point the lever straight up (90 degrees) for semiautomatic, and point the lever back (180 degrees) for full automatic. Or burst. Pretty simple.

One innovation seen occasionally on competition guns is the ‘short-throw’ safety lever. This is a safety lever where semiauto requires less than a quarter-turn of the lever. Usually it’s about a 45-55 degree range of travel that will switch the rifle to semiautomatic.

Something like this has also been seen on some military rifles, including the FN SCAR. On the SCAR’s safety lever, the 45 degree position is semiautomatic and 90 degrees is fully automatic. It’s definitely easier and faster than the standard AR lever, but it’s not really worth fussing about. Unless you’re a competition shooter where every tenth of a second counts, in which case, you can mod your heart out. That said, it’s not a super popular mod on the competition circuit. Usually money gets spent elsewhere.

It becomes a little more interesting when combined with a recent Marine Corps study. The Corps appears to have (re)discovered that fully automatic fire is more effective on moving targets than semiautomatic fire. This is no surprise. We’ve known this for a while now. Recall that the original demand for the rate of fire on the MG-42 came from wanting to maximize hit probability for a target moving from cover to cover at range. And Project SALVO and SPIW were all about increasing hit probability by getting more bullets downrange.

All that said, let’s look at the specific formulation, since we have it for this study. Numbers are always good. To simulate an enemy soldier moving from cover to cover, the marines looked at a man-size target moving at a speed of about 10 miles per hour, at a range of 50-150 yards, and assumed a 2.2 second exposure. They worked out that if a soldier was firing on semi-automatic, the hit probability was about 0.4. This hit probability went up to 0.6 simply by switching over to full automatic.

Anyway, the Marines were a little concerned that by the time the soldier saw the moving target, flipped the selector to automatic, took aim, and fired, the target would be gone. Remember, there’s only a 2.2 second exposure time. So they reached out to Geissele to help. While they were wishing, they also wanted the transition in and out of full-auto to be as easy as possible.

Geissele’s high speed selector starts with a 45-degree position for semi-automatic, and a 90-degree position for fully automatic. Just like the SCAR. What’s new is that the selector is spring loaded. So the marine holds the selector in the 90-degree position with his thumb to fire on full-automatic and lets go when he wants to go back to semi-automatic.

I like the shorter throw, but I’m not entirely sold on the spring-loading. It seems to me like this is the sort of thing that one ought to be able to handle with doctrine and drill. A technological solution in search of a problem. And I really don’t think the short throw is worth the bother.

Recharging in the Field

Here at the Soapbox, I try to talk logistics when I can. While it’s not as sexy as a cool new fighter jet or carbine optic, logistics is a vitally important part of keeping an army going. Today we’re going to look at a few different ways to provide power to all of the electronic devices of the modern soldier.

The SPM-622 is an army-issue battery pack. It weighs one pound, and measures 1.2″ x 3.4″ x 3.2″. It has six bidirectional ports for charging devices or charing the SPM itself. It can be used to charge a wide variety of commercial and military batteries, and it can also directly charge a variety of military radios. As you might expect, it’s also weatherproof and rugged. The SPM even comes with an LCD display to show the status of its battery, plus those of any connected devices.

REPPS (Rucksack Enhanced Portable Power System) is a 62 watt solar cell “blanket” that folds up into a convenient backpack. It weighs about ten pounds and is a good choice for light infantry units. In hostile terrain, moving fuel for generators is expensive, difficult, and dangerous. REPPS reduces the need for fuel convoys.

The Marines wanted something a little bigger than the backpack-mounted REPPS, and developed GREEN: the Ground Renewable Expeditionary Energy Network. It consists of rigid solar cells, stored in protective cases; a power controller; and an array of batteries. With batteries and solar power, GREEN provides a continuous 300 watts. Each solar cell is stored in a 67″ x 36″ x 12″ case, and the cell and case together weigh 145 lbs. The power controller is 23″ x 17″ x 8.5″ and weighs 60 lbs. The batteries weigh 38 lbs. each and measure 13″ x 16″ x 7″. Interestingly, this bigger system is more suited to vehicular carry, and for setup in a more permanent sort of base.


Despite their original design as antitank weapons, most unguided rocket launchers get pressed into service for battlefield demolition work, targeting bunkers and buildings that are used as firing positions. The RGW 90 LRMP was designed to handle a lot more of this sort of demolition work, while keeping some anti-armor capability for moderately armored targets. Which is fine by me; a 90mm HEAT warhead is going to be pretty marginal against most modern MBTs.

The RGW 90 LRMP is a derivative of MATADOR, also known as RGW 90, which is itself a derivative of Armbrust. Armbrust is a contemporary of the American M72 LAW, and like the LAW, it is a single-shot antitank weapon. It’s even about the same caliber. A significant difference is in the operation. The Armbrust puts a propellant charge between two pistons. The front piston pushes the projectile out the front, and the rear piston pushes a bunch of shredded plastic bits. The mass of the projectile matches that of the plastic bits, and the pistons don’t leave the launch tube. This removes the danger of backblast. RGW 90 offers a few different warhead options in a larger 90 mm caliber.

The RGW 90 LRMP (a.k.a Wirkmittel 90) uses a unique, programmable, tandem-HESH warhead with a fragmentation jacket. It’s optimized for blowing up battlefield obstructions and ruining a bunker’s day. It’ll be great in a city, and while it’s going to do plenty of damage to moderately armored vehicles, it’s not the best choice for engaging MBTs. Which is fine. Those tend to be equipped with lots of composite and reactive armor these days. Plus, there are lots of other weapons that look to take down tanks. Few are optimized for demolition.

An electronic sighting unit, made by Hensoldt, is paired with the RGW 90 LRMP. It can be detached and moved from launcher to launcher. The sighting unit handles rangefinding and airburst settings, if desired, as well as elevation adjustments for range. With the electronic sighting unit, Dynamit Nobel claims the RGW 90 LRMP has an effective range of 1,200 meters, which is outstanding. I suspect but can’t confirm that the round uses some kind of rocket assist to reach that range.

The RGW 90 LRMP weighs a bit less than twenty pounds, making it two pounds heavier than the AT4-CS (which is safe to fire in confined spaces) and about five pounds heavier than the regular AT4. However, the AT4 does not feature a programmable warhead, and the AT4 does not have an electronic sighting unit to assist in making accurate long range shots.

Overall, I think the RGW 90 LRMP is a pretty compelling light antitank weapon, with an unusual (and welcome) specialization.

Rak 120mm Self Propelled Mortar

Poland’s Rak 120mm self propelled mortar is the sort of turreted system that Russia has had for years but never really caught on in the west. It’s built on the Rosomak chassis, which is a Polish-made variant of Patria’s 8×8 AMV.

Rak self propelled mortar

In the turret is a 120mm breach-loading mortar. It has an automatic loading system with a capacity for 20 ready rounds. 26 additional rounds are stowed in the hull. The autoloader and mortar has a rate of fire of 6-8 rounds per minute. The mortar has the expected computerized fire control system that is integrated with the GPS/INS navigation system. This fire control system also allows for direct fire with a laser rangefinder and a day/night sight. A coaxial 7.62mm UKM-2000D machine gun is also provided.

Chief among the advantages of a turreted mortar carrier is the ability to provide protection for the crew. The Rak has STANAG Level 1 armor protection all-around, which means it’s rated to resist 7.62mm M80 rounds and 5.56mm M855 and M193 rounds fired from a distance of 30 meters. It’s also proof against fragments from a 155mm artillery shell detonated at 100 meters. That’s pretty good, but I’d prefer a bit more protection. More specifically, I’d be concerned about DPICM-type submunitions hitting the roof, and I don’t expect the Rak to be protected from these.

The Rak has a crew of three, which is notably less than the simpler mortar carriers. That’s good for life-cycle costs. Overall, I like the Rak a lot.

CAS Aircraft Revisited

I’ve spoken before about CAS-specialist aircraft. I’ve spent a lot of time with the virtual A-10 in DCS, and I’m a big fan of the aircraft. In my heart, I love that gun. But the heart can make us do stupid things. We can’t always trust it. Similarly, the A-10 has saved the bacon of a great many American soldiers in combat. They adore the Warthog, and rightfully so. But they would adore any aircraft that saved them.

We want to know whether or not the Dedicated CAS aircraft is a good buy. Keeping it simple, we’ll compare it to buying more multirole aircraft instead. In USAF terms, A-10s or F-16s. Given that this is 2017, and we have combat data on both, is it worth it to put money towards maintaining the A-10 fleet, or should that money be switched over to the F-16s and F-35s?

The close air support mission is a peculiar one, and one full of contradictory requirements. The A-10 seems tailor-made for the mission, with plenty of armor and a massively powerful gun. It’s optimized for flying low and slow, and this kind of flight profile maximizes the utility of the gun and the ability of the pilot to see things.

That sort of flight profile make a number of assumptions:

  1. Local air superiority has been achieved and can be assumed
  2. Enemy air defense is extremely limited in number
  3. Enemy air defense is gun based or nonexistent

In a conventional shooting war, or even a low-intensity conflict with a sophisticated adversary, we don’t get to assume these are true.1 In a COIN conflict, we get (1) and (2) but we may not have (3). The enemy may have access to MANPADS like Stinger or Igla. As seen in the Soviet experience in Afghanistan, this forces aircraft to medium altitudes, i.e. out of the gun envelope.

Let’s look at the combat record. The A-10 has seen combat in Gulf War I as well as providing close air support as part of US military operations in Iraq and Afghanistan. The first Gulf War is as close as we get to seeing the A-10 in a conventional war. The A-10 was not sent in against the Iraqi SAM systems. But it did see plenty of use against troops of both the Iraqi Army as well as against those of the Republican Guard. The Republican Guard was better equipped and better disciplined than the conscript regular army. The Republican Guard did not have much in the way of MANPADS or other short-range SAM systems, but they fought back with guns. Many A-10s sustained combat damage, and two were lost on February 15, which caused A-10s to be tasked to other targets. While the A-10’s armor usually allowed it to make it back to base, the A-10’s lack of speed was identified as a deficiency that made it more vulnerable to gun hits.

The primary tank-killer for the A-10 in the Persian Gulf was the IR-guided Maverick, not the GAU-8/A. Of course, other aircraft can also carry these Mavericks, and these other aircraft also racked up a respectable tally of destroyed tanks with the AGM-65s. The A-10A had very little provision for precision-guided ordnance2, and so did not use laser guided bombs to “plink” tanks, unlike the F-111. Again it doesn’t take a purpose-built aircraft to carry precision ordnance, and these can be delivered from medium altitude, away from AAA and MANPADS.

Lots of aircraft have done CAS duty in Afghanistan, including of course, the A-10. Again, the big star weapon hasn’t been the gun. It’s the JDAM, which are GPS guided. Also using the JDAM to excellent close air support effect are the B-1B and the B-52H. And many others too, but I’m highlighting heavy bombers because they’re big, high-altitude behemoths that aren’t really “designed” with CAS in mind. But they can do it with modern weapons. As can F-16s, F-15Es, F/A-18C/Ds, F/A-18E/Fs, and just about every other multirole tactical aircraft you care to name. Tactical aircraft give up the giant gun and the armor plate. But there’s a net gain in survivability from more speed because they can evade missiles better, and they can perform the vast majority of modern CAS missions just as well as a purpose built type.

For COIN, one might be tempted to look for savings in aircraft types. These can be provided from UCAVs like the MQ-9 Reaper or from something like a Super Tucano. Both of these will provide more sorties per dollar than the sort of big armored CAS-optimized plane. And if there’s negligible threat, they’ll drop precision guided munitions just as well.

Against a hypothetical, sophisticated opponent with modern integrated air defense systems, all of the above will all require large strike packages to approach any kind of reasonable survivability level, and those aren’t feasible for CAS. Maximum survivability is provided by aircraft with low-observability characteristics, such as the F-35 or F-22. In Desert Storm, coalition air commanders had faith only in the stealthy F-117 to penetrate the formidable air defenses around Baghdad. The alternative to stealth is a big, Rolling Thunder-style strike package with ECM and SEAD escorts, plus fighter escorts. Which isn’t going to be generated for an aircraft to loiter in support of ground forces.

Let’s look at a more modern example: recent events in the Ukraine. Here’s a radar map of the Ukraine.
ukraine air search radar map
That’s a map of all of the air search radars in the region. Have fun with that. And remember, lots of these SAM systems are going to be reasonably modern units that can move. Everyone saw the success the Serbians had by shutting off their radars and moving their air defense systems around to frustrate NATO SEAD strikes. And you can’t sortie your A-10s until you get air superiority and deeply reduce that SAM umbrella.

The gun on the A-10 is a fantastic weapon, but it’s a trifle outmoded these days. If a gun and armor were the sine qua non of CAS, we’d sortie Hs 129 B-3s. With modern precision munitions, the role can be filled by multirole or low-observable-multirole types with no loss of effectiveness. And in hostile airspace where the opponent has some actual air defenses, the A-10 and its ilk are the least survivable types. A mess like the Donbass is begging for low-observability if you want to actually survive to deliver ordnance and live to strike again tomorrow.

  1. Cf. MH 17. 
  2. Rectified on the A-10C. 

American Mortar Carriers

Mortars are awesome, and a bigger mortar means more range and explosive power per shell. But a bigger mortar is a lot harder for troops to carry. The biggest commonly in use today are the 120 mm mortars like the Soltam K6. This weighs 319 lbs, and breaks down into the following components:

  • M298 cannon assembly (110 lbs)
  • M190 bipod assembly (70 pounds)
  • M9 baseplate (136 pounds)

That’s not going to be easy for infantry to haul. And it’s pretty natural, especially for motorized or mechanized infantry, to want to put mortars in a carrier vehicle. Let’s look at a couple American options. The basic idea here is pretty straightforward: take an APC, fit a retractable roof, and mount the mortar in the back. Surprisingly simple for units in the US Army inventory.

Our first example is the M1064. It’s based on the classic M113 APC. While the M113, even with the A3 improvements, is pretty vulnerable to modern battlefield threats these days, in the artillery role it’s perfectly adequate. The mortar is the 120mm M121, an American licensed copy of the K6. The M1064 also has a ring mount for a machine gun, and usually has an M2 mounted. Ammunition capacity is 69 mortar shells and 600 rounds for the M2.

The Israelis operate a similar system to the M1064, the Keshet. The key difference is that it’s equipped with the CARDOM mortar system, which automates the aiming of the mortar using a computerized fire control system. I would expect the number of stowed shells carried to be similar to the M1064.

Next we have the M1129, based on the Stryker APC. Again, there’s a retractable roof exposing a 120 mm M121 mortar. Some versions are also equipped with an additional, smaller mortar for dismounted use. This may be a 60mm or an 81mm mortar. If the M1129 is only equipped with a 120mm mortar, it will carry 60 120mm mortar shells. If a dismountable mortar is also carried, the supply of 120mm shells is reduced to 48. If a 60mm mortar is carried, 77 shells for it will be carried as well. On the other hand, if an 81mm mortar is carried, a supply of 35 shells will be provided for it. Note that if a dismount mortar is provided, this mortar cannot replace the 120mm for mounted use, and the vehicle crew is sufficient to use only one of the two provided mortars.

Here’s a handy chart of ammo capacities. The designations M1129-60 and M1129-81 are my own, used here for convenience. What dismount mortar, if any, is carried on an M1129 is based on its tasking in the organization table (i.e. whether it belongs to a rifle company, rifle battalion, or RSTA1 squadron) and is not indicated in its designation.

120mm shells69604848
81mm shells35
60mm shells77

In terms of deployment, each company in a Striker Brigade Combat Team has two M1129-60s and each battalion has four M1129-81s as an organic component. An RSTA squadron gets six M1129s. A mechanized infantry battalion will get 6 M1064s. In the future, an AMPV-based mortar carrier will replace the M1064.

  1. Reconnaissance, Surveillance, and Target Acquisition. They’re organized in the cavalry model (hence “squadron” instead of “battalion”). One RSTA squadron functions as the recon element for a brigade. 

There Is No Milspec AR-10

Anytime I hear the words “milspec AR-10” my teeth get set on edge. There’s no such thing. I’m gonna repeat that.

There is no such thing as a “milspec AR-10”.

Got it? It should be pretty clear. No. Such. Thing.

Let’s start with what exactly is “milspec.” You may have guessed it’s short for “military specification,” and you’d be correct. For the US Army (and some others), they like to take ownership of certain products. Sometimes there are competitive bids. For the M4, there’s a specification of what exactly an M4 is, and then the US Army can have companies bid on how much it will cost to make a certain number of rifles to that spec. The milspec is owned by the military (in general).

So there’s no “milspec AR-10” because no major military adopted the AR-10 and cemented the design that way. Emphasis on the and. Merely adopting the rifle is insufficient. The AR-10 was used by the Sudanese, Cubans, and the Portugese, but none of those made a spec. All of those arms were built by Artillerie Inrichtigen, which wasn’t able to get more contracts and stopped making AR-10s ages ago. Still no spec.

Things got confusing in the 1990s. By that time, Eugene Stoner was working for Knights Armament, and they made the SR-25, a modern take on the AR-10 design for use as a semiautomatic marksman’s rifle. This used the gas system improvements worked out on the AR-15 and had a number of parts shared with the then-issue M16A2. The magazine design is also used in DPMS’ AR-10-pattern rifles, among others, and you can find these magazines as “DPMS/SR-25” pattern.

There’s another pattern of magazines currently in use for AR-10-pattern rifles. This one is made, confusingly enough, by Armalite. The original Armalite company ceased operations in the early 1980s. The rights to the name were bought, and Armalite was relaunched in 1996, with a new AR-10 pattern rifle (among other things). At that time the 1994 Assault Weapons Ban was in effect in the United States. This bill prohibited the sale of new magazines with a capacity of more than 10 rounds, but older magazines that held more than 10 rounds could still be bought and sold. So (new) Armalite made magazines that had a common design with M-14 magazines, so buyers of their rifle could use existing, common M-14 magazines with a couple easy modifications. These are “Armalite” pattern magazines, and they’re not compatible with DPMS/SR-25 pattern magazines.

And no, neither DPMS nor Knights nor Armalite are responsible for any current milspec “AR-10-pattern” rifle.

Generals Balck and von Mellenthin on TO&Es

In the late 1970s and early 1980s, the US Army invited two of the best tank commanders of the Wehrmacht, General Hermann Balck and his Chief of Staff General Friedrich von Mellenthin, to come to the US Army War College in Carlisle, Pennsylvania for several seminars and war games. Balck and von Mellenthin had a great time playing with the huge amount of airpower available to them while playing as BLUFOR. In addition to comparing notes on wargame solutions, the US Army asked Balck and von Mellenthin a number of questions about organizing units. Here’s what they thought was best:

  • Company Strength: Not more than 70-80 men
  • (Rifle) battalion strength: about 300 men
  • Rifle battalion should be broken up into three rifle companies and a machine gun company
  • Panzer division should have three panzergrenadier regiments and one panzer regiment
  • Panzergrenadier regiment should have two battalions
  • 10 tanks per tank company
  • Tank platoons should consist of three tanks

These units are small. But both of the veteran generals felt that small units were easier to lead and more flexible. Plus, these two generals achieved their greatest successes against the Russians when commanding the 11th Panzer Division when the division was so understrength that it was roughly the size of a brigade, at least as far as number of tanks and combat troops was concerned.

That said, I think Balck and von Mellinthin have gone a bit too far in advocating for small, agile units. While they did an excellent job with small units late in the war, no nation has actually gone this far in cutting unit size. Or really, all that close. You end up needing numbers of men to hold terrain, or to fight in cities.

MRE Quirks

The American MRE is the standard ration for the US armed forces, and is also frequently deployed as aid to areas affected by natural disaster. The MRE came with some interesting innovations when it was introduced in 1981, and many of these have spread to other nations’ rations. Let’s take a look.

Calorie Accounting
The contents of one MRE, as you might have gathered from the name, are intended to be one meal. Or, one third of a soldier’s calorie and nutrient needs for one battle day. One entree, one side, one powdered off-brand Gatorade clone, etc. Most other nations’ rations are accounted for by day. So one package contains two or three entrees, three sides, maybe a snack. I have no idea where this difference came from. Maybe it’s a metric/imperial thing.

Retort Pouches
The classic ration uses cans to store the various components. This is pretty common among older rations, and is still popular today. Cans are pretty old school and easy to make. You can heat things up right in the can, and they can be used to make all kinds of improvised stuff. The MREs are different, using retort pouches to store food instead of cans. A retort pouch is a pouch made from layers of metal foil and various plastics. Food can still be heated up in them, either by immersing them in hot water or with the ration heater. They’re still sealed, just like cans. They weigh less than cans. They don’t make a clanking sound when a bunch bang around in a pack on a long march. Oh, and they require less energy to make. Although these are slowly spreading, especially among the Commonwealth nations, I don’t know why these aren’t more popular. Retort pouches rock.

Ration Heater
Everybody provides some means to heat the food in their rations. Usually, it’s a knockoff Esbit stove with some fuel tabs and matches. It’s fire. Fire is good. But fire leaves obvious traces. So the US military did what it usually does, and came up with a solution. The result is the flameless ration heater. No visible flame. No smoke. It’s a plastic pouch with some magnesium, iron, and salt in it. Add water, and it’ll get really hot. Hot enough to heat your rations. The spec says it’ll heat an 8 ounce ration entree item up by 100 °F in twelve minutes. They’re a really neat little piece of equipment, and lots of fun to play around with. They’re also super easy to use. I really like the flameless ration heater.

The Tabasco bottle
An offshoot of the program to improve MRE menus is including a small bottle of Tabasco sauce. The Army, after spending millions1, finally figured out that being able to control how spicy a dish was played a big factor in how much people enjoyed a dish. So they added a small bottle of Tabasco2 sauce to some, but not all, of the MRE menus. Progress. All that said, while I really like this idea, it would be better if it was in all of the menus.

  1. They could have grabbed a few chefs, or even a few diner cooks, interviewed them over a few beers and gotten the exact same information. But leave it to Big Army to do it the spendy way. 
  2. Actual, name brand Tabasco sauce! Unlike most things in an MRE, this is a brand you’ll recognize, not some knock-off. 

Mk 153 SMAW

In the early 1980s, the Marines were looking into light antitank weapons. They had the M72 LAW and the AT4, both of which were solid disposeable rocket launchers. However, they were limited to a single warhead type, and Vietnam had showed the utility of reusable systems, like the old recoilless rifles. So they went shopping. They settled on a variant of the B-300 rocket launcher, originally developed in Israel. A number of changes were made, resulting in the Mk. 153 SMAW.

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