Author Archives: parvusimperator

Giant OTV/IOTV Weight Chart

I do like playing around with weight accounting, and I do like tinkering. The following charts were pulled from a US Army service manual1 on the Interceptor Body Armor System. They’re remarkably annoying to find online in detail, and details are important. Especially if you want to play with your own configurations. So in the interest of knowledge and thoroughness, the charts are reproduced here. All weights below are in pounds.

First, the Outer Tactical Vest. This is the vest you see in early Operation Iraqi Freedom Photos.

ComponentXSSMLXLXXL3XL4XL
Base vest6.646.957.668.389.519.8410.8111.79
Throat Protector Assy.0.250.250.250.250.250.250.250.25
Yoke and Collar Assy.0.900.951.001.101.201.301.401.50
Groin Protector Assy.0.700.700.700.850.850.850.850.85
DAPS5.505.505.505.505.505.505.505.50
ESAPI Plates (pair)7.609.5010.9012.5014.2014.2014.2014.20
ESBI Plate Carriers (pair)2.802.802.802.802.802.802.802.80
ESBI Plates (pair)5.105.105.105.105.105.105.105.10
Total System Weight29.4931.7533.9136.4839.41>39.8440.9141.99

Next the Improved Outer Tactical Vest, Gen I. This reconfigured the armor a bit and added a quick release system for easier medic access to a wounded soldier, among other features. Note also the addition of some long sizes, and that the Axillary protection system (the A in DAPS) and the carriers for the ESBI side plates are now integrated into the IOTV base vest.

ComponentXSSMMLLLLXLXLLXXL3XL4XL
Base Vest9.019.339.8610.6010.9711.2411.9812.5113.5215.8016.17
Front Yoke/Collar Assy.0.560.560.560.560.560.560.560.560.560.560.56
Rear Yoke/Collar Assy.0.800.830.880.880.910.910.960.961.021.171.17
Groin Protector Assy.0.720.720.720.720.870.870.870.870.870.870.87
Lower Back Protector Assy.0.670.670.670.670.670.670.670.670.670.670.67
Deltoid Protector Assy. (pair)2.002.002.402.402.402.402.902.902.902.902.90
ESAPI Plates (pair)7.609.5010.9010.9012.5012.5014.2014.2014.2014.2014.20
ESBI Plates (pair)5.105.105.105.105.105.105.105.105.105.105.10
Total System Weight25.4628.7131.0931.8333.9834.2537.2437.7738.8441.2741.64

Finally, we come to the Improved Outer Tactical Vest, Gen II. This vest brought a bunch of minor improvements.

ComponentXSSMMLLLLXLXLLXXL3XL4XL
Base Vest9.619.9310.5611.3011.7211.9912.7813.3114.3216.6016.97
Front Yoke/Collar Assy.0.560.560.560.560.560.560.560.560.560.560.56
Rear Yoke/Collar Assy.0.800.830.880.880.910.910.960.961.021.171.17
Groin Protector Assy.0.720.720.720.720.870.870.870.870.870.870.87
Lower Back Protector Assy.0.670.670.670.670.670.670.670.670.670.670.67
Deltoid Protector Assy. (pair)2.002.002.402.402.402.402.902.902.902.902.90
ESAPI Plates (pair)7.609.5010.9010.9012.5012.5014.2014.2014.2014.2014.20
ESBI Plates (pair)5.105.105.105.105.105.105.105.105.105.105.10
Total System Weight27.0629.3131.7932.5334.7335.0038.0438.5739.6442.0742.50

That’s as far as this copy of the manual goes. Probably for the best. That’s more than enough tables for one day.


  1. TM 10-8470-208-24&P 

Ballistic Combat Shirt

Body armor. Don’t go outside the wire without it, right?

The upper thoracic cavity is where the heart and lungs are. That’s what we’re trying to protect. And hard plates like ESAPI do a good job of protecting the front and rear of the upper thoracic cavity. The sides get more difficult, because you have arms. There’s still a lot of important blood vessels, and rather complicated joints in the area above and to the sides of where plates go, regardless of whether you are wearing an armor carrier like the IOTV or a simpler plate carrier rig.

The IOTV comes with a number of accessories to protect the neck, collarbone region, shoulders, and the sides of the upper thoracic cavity. These components are the yoke and collar assembly and the Deltoid protector. These consist of an inner soft armor component, an outer cordura casing, plus attaching hardware. In size L the total weight of these accessories is 3.87 lbs.

We can contrast that with a ballistic combat shirt. This is the usual modern style of combat shirt, with heavier material for the sleeves and upper torso and lighter material for the abdomen, that’s designed for (somewhat) more comfortable wear with body armor. In the BCS, the upper chest and shoulder region contains segmented soft armor panels, providing the same ballistic protection as the aforementioned yoke and collar assembly and the deltoid protector, but the total weight of a size L Ballistic Combat Shirt is only 3.2 lbs. This looks like about half a pound of weight savings, but remember, this includes the combat shirt. A modern-style combat shirt sans armor weighs about 0.9 lbs.1 So, for system weight, we’re looking at more like 1.4ish lbs. of weight savings. Not a lot, but every little bit helps.

Weight savings isn’t the only gain here. We’re removing a lot of bulk from the shoulder area, which is a big win in terms of how much it sucks to wear. Deltoid protectors get caught on things. They make narrow doorways, crawlspaces, and vehicle hatches more annoying to move through. Less bulk means you can move through these areas faster. The bulk also makes weapon manipulation more annoying. In testing, soldiers unanimously praised the new ballistic combat shirts for being less bulky and annoying. The loss of the various straps and buckles to attach all the above components is probably also a big hit.

It’s often very difficult to reduce soldier load by reducing protection for the regular “line” infantry. Special forces guys play by different rules, but the regular grunts are usually stuck with a heavy load. Sometimes it takes some out of the box thinking to be able to make some small gains.


  1. Source here, though they don’t tell me size. Shouldn’t matter much though. “A bit less than a pound is probably a fair approximation for most modern NyCo shirts with this style of cut and a flame-resistant treatment. 

Body Armor Ratings

Body armor toughness comes in a bunch of different flavors. Over here in the US, we have a couple standards. There’s the National Institute of Justice (NIJ) standards, standards used by the US military, plus a bunch of other marketing-speak. Let’s break it down.

First, NIJ:

TypeProtection
Level II9x19mm (124 gr. FMJ @ 1,305 fps), .357 Magnum (158 gr. JSP @ 1,430 fps)
Level IIIA.357 SIG (127 gr FMJ @ 1,470 fps), .44 Magnum (240 gr. SJHP @ 1,430 fps)
Level III6 rounds 7.62x51mm M80 (148 gr. FMJ @ 2,780 fps)
Level IV1 round 7.62x63mm (.30-06) M2 (166 gr. AP @ 2,880 fps)

NIJ ratings are commonly used for armor marketed to law enforcement and civilians. Some notes:

  • All velocities listed above are approximate, and should be understood to be +/- 30 fps.
  • Level II and IIIA are soft armor, and are understood to be reasonably multihit.
  • Level III and IV are hard plate armor.
  • Level IV is required to be able to withstand at least one round of 7.62x51mm M80 FMJ. It is not required to meet Level III multihit standards (6 shots) against M80.
  • You may notice there is no testing required against SCHV rounds (e.g. 5.56x45mm, 5.45x39mm). Level III armors may or may not stop SCHV rounds. Level IV armors are required to stop at least one SCHV round.

This last point leads lots of manufacturers to test against various SCHV (usually 5.56mm in the States) rounds, which is good. Do note that “Level III+” and “Level III++” are not NIJ certifications. Those are marketing nonsense. Read the list of test rounds carefully. Some materials used for Level III plates have problems with M855 steel-core (semi-armor piercing) rounds, and some other materials used in Level III plates have problems with the speed of M153 rounds, especially out of a 20″ barrel. Ideally, your plate will withstand both.

What about military plates? I can only speak for the US plates at present. These plates are made from ceramic materials. The US Military uses its own testing standard, not the NIJ one. SAPI1 plates are designed to resist three hits of “up to” M80 7.62x51mm ball. There’s also ESAPI2, which has a similar multihit standard against M2 .30-06 AP rounds. And then there’s XSAPI. Because somewhere out there, some terrorist has some exotic high power super armor piercing 7.62x54R mm that will punch through ESAPI plates and we need to stop that round too. It’s also multihit. Against something exotic, but I don’t know the test round. Maybe tungsten-cored .30-06?

Anyway, as you’d expect, more protection means more weight:

SizeDimensionsSAPI WeightESAPI weightXSAPI weight (Approx)
XS7.25″ x 11.5″2.8 lbs.3.75 lbs.4.7 lbs.
S8.75″ x 11.75″3.5 lbs.4.6 lbs.5.8 lbs.
M9.5″ x 12.5″4.0 lbs.5.5 lbs.6.9 lbs.
L10.125″ x 13.25″4.6 lbs.6.3 lbs.7.9 lbs.
XL11″ x 14″5.3 lbs.7.2 lbs.9.0 lbs.

Do note that all US Military plates assume they are mounted over the OTV, IOTV, or equivalent military-spec soft armor for them to perform as advertised. To the best I am able to determine, XSAPI plates have never been deployed in combat. They sit in depots because they’re too damn heavy and because the expected threat never materialized. Also, remember the above is per plate. Double it.

That military soft armor is tested to a different standard than the NIJ one. The military is concerned with fragmentation, primarily, so they look at the V50, i.e. the speed at which a given projectile must be going to have a 50% chance of penetration. This number is chosen because it’s a lot easier to work with than V0 from a measurements and statistics perspective. To simulate artillery fragments, the US Army tests with steel projectiles with weights of 2, 4, 16, and 64 grains. Steel doesn’t deform like lead pistol bullets do, so this is sort of a different challenge than regular pistol bullets. The V50 for a 124 grain 9mm NATO round against the current soft armor in the IOTV is about 1,525 fps, which is pretty similar to that of most Level IIIA soft armor panels. On the other hand, the NIJ requires Level IIIA panels to also stop .44 magnum rounds, and the US Military doesn’t.

Next time, we’ll take a more in-depth look at soft body armor systems.


  1. Small Arms Protective Insert 
  2. Enhanced Small Arms Protective Insert 

Parvusimperator Reviews a Remington 870 Police Magnum

I have some local trainer friends who teach a well-regarded shotgun class. I decided to take it to learn some things about how to use a scattergun, which of course meant that I needed a shotgun. My choice was a cop trade-in Remington 870 Police pump-action shotgun. At first, this might seem like a very un-Parvusimperator choice, so let’s review the reasoning.

  1. It was cheap. I picked this thing up for less than half the MSRP of a brand-new 870P. So I’m getting to class on the cheap, which is nice when I’ve burned through my training budget and am saving for a fancy USPSA Open pistol.
  2. It’s quality. The 870P is made with better parts than a regular 870, and this one is old enough to date from back before the “freedom group” axed Remington’s QC department in search of greater profits. So I have a cheap, reliable gun that I won’t have to worry about going wrong mechanically in class.
  3. I like the idea of taking an old, beat up shotgun and making it mine. Sort of like adopting a pet, but for guns.
  4. If I ended up disliking it, I could probably get all my money back selling it, given that I bought the gun used and that it’s a desirable Police model 870.

Upon unboxing, I discovered my shotgun was as expected. Date codes on the barrel told me the shotgun was built in 1995. In the meantime, the synthetic furniture on it had been beaten to hell and back. Someone had gouged “VAULT” in the stock. The ‘brass bead’ sight no longer had any finish resembling brass. The receiver was well-patinaed, and had a good bit of rust.

On the plus side, all of the metal is sound, and the action is very smooth. Running it is a joy, and brings a smile to my face. Also, I have no complaints about the trigger. It’s not something superfancy, but it also has no glaring problems.

I didn’t have a ton of time to get the shotgun ready for class. Clearly, I wouldn’t be able to get it cerakoted or anything, and I was expecting class in the rain. I did have time to make a couple changes in preparation. Did you really think I would not? I added a Magpul SGA-870 stock and a Wilson Combat +2 extension.

I’ve talked about the Magpul stock before. But it bears talking through again. Magpul put a lot of thought into this stock. It’s the best stock out there for shotguns. It’s super comfortable and is easily adjustable for length of pull. I’m not a tall guy, and I don’t have gorilla arms, so I normally get very annoyed at the very long length of pull on factory stocks on shotguns. They’re probably “tradition” or some nonsense.1 Anyway, problem solved, problem staying solved. It also comes with a nice rubber recoil pad. Replacing the old rubber recoil pad is something that should be done on general principle given the age of the shotgun and how much abuse the old stock had gone through. As a bonus, the stock came with some sling attachment points.

Lots of people make magazine tube extensions. I picked the Wilson one because the price was reasonable, the quality is good, and it came with all of the other extras I wanted, namely a new high-visibility follower, a new magazine spring, and a front sling attachment point. The high-visibility follower is very helpful in a class environment for administratively verifying that the weapon is unloaded. Even if I didn’t get the magazine tube extension, I would have wanted to replace the magazine spring because I don’t know the age of it.

On to class! How did the shotgun do? What did I learn about the parts? And what is coming for our rescued shotgun?

My shotgun ran great in class. Several others had shit break on their guns. One guy had the handguard become detached from the loading forks. Another had a screw come loose inside his receiver and jam things up. People switched to backup guns. But my old 870 Police Magnum gave me no trouble at all. Despite being old and unproven (to me), I had a great time with my shotgun, and my small initial investment paid off.

My existing mods were also good choices. My instructor friends are also huge fans of the Magpul stocks. I found that it did everything I asked. I got the length of pull adjusted to suit my preferences, and that helped. The stock even made supporting and firing the gun one-handed reasonable.

I also had no complaints about the extension. More ammo is better. Duh. The spring worked great. No jams. Plus, the high visibility follower was in fact very visible.

What I did find unsatisfactory was the two-point sling. I rigged this up like I would rig up one of my carbines, using a VTAC sling. This wasn’t my best build plan ever. Having a sling mounted in front of the handguard on a pump shotgun ended up being super annoying, because it seemed like it was always getting in the way. Plus, the shotgun always felt askew when it was hanging on the sling. On a carbine, I’d just move the sling adapters, but I can’t do that here. This will take some more thought.

The ‘formerly-brass’ bead sight on the shotgun was a reasonable sighting system. It wasn’t great. For most “indoors” distances, it will work fine if you’re using something with a pattern like non-flite-control buckshot or birdshot. I found that at distances, the lack of a good second reference made headshots with slugs harder to achieve than I would like. I will probably end up getting the shotgun drilled and tapped for a picatinny rail so I can mount a small red dot. Because I freaking love red dots, and I love the target-focused shooting paradigm that they get you into.

While the gun worked great, there are things that need changing. I’ve talked sights, even if those are “wants” more than needs. A bigger priority is the finish. The one on the gun is toast. When I asked gunsmiths in the class about getting the rust off, they told me not to worry about killing the finish, because it’s already crap. Not that 870s are known for their good factory finishes.2 This is going to get redone in…something. I don’t know what yet. Stay tuned.


  1. Ask Fishbreath. 
  2. Seriously, how does Remington’s parkerizing suck so hard? My M1 Garand also has a parkerized finish on its metal parts, and it’s a bit more than twice as old as my 870, and the finish on my M1 is fine. No rust. 

Parvusimperator’s Submachine Gun Roundup

At a recent class I had the great pleasure to fire a number of submachine guns. Yes, with happy switches. Here are my impressions of several models that I got a chance to put a bunch of rounds through.

I would like to thank Washington County Machine Guns for providing the hardware to make this possible. If you’re in or near Southwestern Pennsylvania and would like to shoot some automatic weapons, check them out. They’re awesome!

M1A1
This was an honest-to-goodness World War II vintage Tommy Gun. Freaking awesome. Without the long barrel for NFA rules, it balances reasonably well. It’s heavy, but not unbearably so. Note that I’m not lugging it around Guadalcanal, so I didn’t have much of a chance to complain. On full auto, the weight is the greatest thing ever. The Thompson was very controllable and easy to keep on a 1/3-size IPSC steel target. Sights were simple but effective. Oh, and the magazine release is goofy, but the 1920s were a strange time. Regardless, it was great to have some time with this touchstone. Fist bump for my grandfathers who got to kick the (actual) Nazis out of France with these.

Sten Mk. III
This one is weird. Crude but effective. The machining work isn’t very nicely done, but it’s sturdy. There isn’t really any attention paid to ‘fit and finish,’ but I didn’t feel like I was going to break it either. There’s a nice big reciprocating mass to help you fight recoil. The side-mounted magazine is kinda goofy, and there’s no good place to put your hand. The skeleton stock isn’t very nice to hold either. That said, while it felt weird to shoulder, it was very controllable. No doubt helped by the smaller caliber. And, while lighter than the Thompson, the Sten benefits from a softer shooting round. More death to the mini IPSC steel!

HK MP5-N, suppressed
Oh hell yes. John McClain, here I come! I can see why this gun is so loved among people who use these things for a living. Being the only closed-bolt weapon, single shots were super precise, as were the opening rounds of a full auto volley. This gun had great build quality. It’s heavy enough to help with recoil management, but not so heavy that it’s awkward to manipulate. Controls are generally well thought out, though the ergonomics aren’t quite AR-15 good. Also, the HK Slap is fun to do. Yippie-kai-yay, motherfucker.

Glock 17 Conversion
This is not technically a Glock 18. It is a Glock 17 converted to fire full auto only. And it shoots as fast as the Glock 18 at an awe-inspiring 1,200 rounds per minute. Yes, 1,200. Just like an MG42. And no, it’s no heavier than a normal Glock. This was one of two guns that was a grip check. Gotta get behind it and have proper technique, or this gun will take you for a ride. It also induces maniacal laughter like nothing else. The Full-Auto Glock is much harder to keep on target, but very easy to suppress things with. Or scare people with. Or clear a hallway. Protip: Start with 3-5 rounds in a magazine just so you can get a feel for this thing.

FN P90
I got to try a PDW in the unneutered, as-designed way: spraying lots of little bullets. This thing is small and super controllable. I can understand the concept a little better now. It felt like I was spraying a swarm of bees at the target. Tiny, high-velocity killer bees. Recoil isn’t really a thing given the weapon weight and the energy of the 5.7mm cartridge.

Walther MPK
Another weird one. Looks kinda goofy, had a very cheap feel to it. The sights on the Walther are stupid. Ergonomics were odd. It was still controllable, but it was not very comfortable in the hand. Again, seeing this stamped thing and then comparing it to the MP5 shows how amazingly good HK’s 9mm wondergun was.

FN FAL, SBR
Take a big ol’ Belgian FAL. Cut that barrel down to about eight inches or so. Flip the selector switch to “Rock and Roll”. Question the wisdom of giving the skinniest guy on the range a very cut down battle rifle. Carefully set yourself up behind the gun. And then get knocked around anyway, because I’m new at this. But it’s not like any of the heavy guys had an easier time with this, because easy to control this ain’t. Nothing highlights your technique issues in a hurry like trying to wrestle a bronco with a jetpack. Or shoot a short barreled .308. This thing is a beast. A normal FAL is too, but less weight and more concussion does not make this thing any easier to control. On the other hand, it was super fun to shoot. More giant grins.

In fact, this entire exercise was full of giant grins, cackling, and good times.

Resurrected Weapons: LOSAT/KEM/CKEM

I’m lumping these together because they all operate on the same basic principle, and are really just different sized versions of the same concept. This idea keeps coming up in a bunch of different sizes and a bunch of different guises.

Antitank missiles today use shaped charge(s) to penetrate armor. We might call this a “chemical energy” method of penetrating armor. More technically, we might call it the Munroe Effect. This is really effective, and doesn’t depend on missile speed. However, there are lots of technologies today to counter this method of armor penetration, including reactive armor (both explosive and non-explosive types), spaced armor, various forms of composite armor, and cage armor. And we can mix and match the above to get some really hard to kill vehicles.

That said, the clever observer will note that most tank guns today use some kind of APFSDS round, a kinetic energy penetrator. Heavy alloy dart moving very fast. Present armor technology makes this a lot harder to defeat than a shaped charge. LOSAT (later renamed KEM) and CKEM would try to apply this same warhead type to an antitank missile. Start with a heavy metal warhead, add a big honking solid fuel rocket motor and fulfill your need for speed.

The missiles were a little different. MGM-166 LOSAT/KEM was 2.85 m long, 16.2 cm wide, and weighed 80 kg. It had a top speed of about 1,500 m/s or 5,000 fps. At this speed, it reached its maximum range in under 5 seconds.

CKEM is the newer, Compact version of the concept. It’s also faster because of rocket motor improvements. It was build in the late 90s/early 2000s to fit a roughly TOW-sized footprint. CKEM was a little longer than TOW at 1.5 m, but matched it’s 15.2 cm diameter. Maximum speed was Mach 6 (about 6,700 fps or 2,047 m/s).

This ends up being a great idea for a number of reasons. We’ve already mentioned that it’s a lot harder to protect a vehicle against APFSDS type rounds. In this case, there is no replacement for velocity. You’ll need heavy armor to stop what’s incoming. Further, a lot of the complicated guidance systems can be done away with. Both missiles had minimal guidance, and relied on lead computations in the launcher to account for any target movement. Given the speeds involved, this is more than sufficient. Finally, being a very fast moving, relatively unfragile thing, it’s a lot harder for modern active protection systems to defeat. All big wins.

Downsides? Well, most of the development and system cost is the motor. We need a relatively small engine that can deliver a lot of thrust very quickly and will also remain stable in storage. That’s not really insurmountable, or a terrible cost driver. Especially when compared to the high-end thermal-imaging based fire and forget systems around these days. The other obvious problem, which doesn’t come up in documentation I’ve seen, is minimum ranges. Even a really high impulse motor will take some time to accelerate that missile up to speed, so there’s going to be a dead zone where the missile will not work as advertised. I’d also expect the motor to be bulky.

Bulk, even for the smaller CKEM, is still an issue. It’s certainly not man-portable. But it would make an excellent antitank missile for vehicles. A JLTV, or a Bradley would make a great carrier vehicle for these. We love tanks, and thus we love antitank missiles. Just like the Russians, who have new tanks. As do the Chinese.

Also, I’d love to see these trialed from helicopters and aircraft. The size isn’t terrible, and the speed should help with the fire control problem.

Verdict: Funding approved by the Borgundy War Department Army Ordnance Board

Project LSAT Weight Comparisons

As a follow-on to my earlier post analyzing the LSAT project, I provided this table with the best comparative data that I can find. Note of course that LSAT systems are prototypes, and weights might change should these come into production. All LSAT data is for the more successful polymer-cased, telescoped (PCT) rounds.

First, the machine gun table:

WeaponM249 SAWStoner 96LSAT LMGM240BLSAT GPMG
Unloaded Weight17 lbs10.5 lbs9.4 lbs27.6 lbs14.7 lbs
Caliber5.56 NATO5.56 NATO5.56 PCT7.62 NATO7.62 PCT
Ammo weight (200 rd belt)6.92 lbs6.92 lbs3.8 lbs13.4 lbs7.5 lbs
Loaded Weight23.92 lbs17.42 lbs13.2 lbs41 lbs22.2 lbs

The 6.5 mm PCT round is very nearly the same size and weight as the 7.62 mm PCT round, so the 6.5 is omitted for simplicity. This also provides a better comparison with the existing M240B. A 200 round belt was used for ease of comparison, though 100 round belts are also commonly used.

Now, the carbine table:

WeaponM4 CarbineLSAT Carbine
Unloaded Weight6.5 lbs6.5 lbs
Caliber5.56 NATO5.56 PCT
Ammo weight (30 round magazine)1.05 lbs0.69 lbs
Loaded Weight7.55 lbs7.19 lbs

The carbine designs are less well developed. I don’t have enough data on the prospective 7.62 mm/6.5 mm PCT ‘battle rifle’ to include it in the table (specifically, I lack the weight of a loaded magazine). We can see that the weight savings are much less significant here, amounting to 2.5 lbs for a standard combat load of 210 rounds. Which is nice, but not quite as massive as the savings for machine gunners.

The General Issue Plate Carrier

The standard wisdom for current infantry protection is to use rifle plates and an armor carrier, which provides fragmentation protection for more area of the torso than the plates do. The armor carrier means that the lower abdomen, area around the plate, and the shoulder straps are going to be rated against fragments. Of course, this comes at a bulk and weight penalty. In Afghanistan, US special forces often took to wearing plate carriers. Plate carriers carry only plates. No soft armor panels, besides optional armor backers. They’re a lot lighter and less bulky. For mountain operations, this is awesome. Of course, there’s basically no artillery threat in Afghanistan. Let’s look at whether or not this makes sense in the general case.

We’re going to compare the IOTV with front and rear plates to a lightweight plate carrier with front and rear plates, specifically the Crye JPC. For the IOTV, we’re not going to include side plates and carriers, since the plate carrier we’re choosing doesn’t come with side plate pockets. Also, these plates provide protection for the abdomen, not the upper thoracic cavity, and the abdomen is a much less critical area. Both would need supplemental protection for the neck, shoulder, or groin. Removing accessories simplifies the comparison a little.

As usual, we’ll be using medium size items for comparison. We’ll also be using a pair of ESAPI plates for both. Two ESAPI medium size plates weigh 10.9 lbs. The medium size IOTV weighs 10.56 lbs. The medium size Crye JPC weighs 1.3 lbs. Since we’re using ESAPI plates, which require plate backers, we’ll need to add those, which gives us another 2.4 lbs.

So we might break this down into three options. The IOTV alone weighs 10.56 lbs. The JPC with plates weighs 14.6 lbs. The IOTV with ESAPI weighs 21.46 lbs. So switching to a a plate carrier with plates instead of an armor carrier with plates saves us about seven pounds in our example, though the exact weight will vary if we choose different models.

Clearly, the armor carrier with plates and plate carrier with plates are both going to be very effective against most rifle rounds. Also clearly, the plates will stop fragments that hit them. The armor carrier will provide fragmentation protection around the abdomen, around the border of the ESAPI plate and on the shoulder straps. Weight for marginal hit protection is what’s in question here.

Overall, I’m inclined to favor the plate carrier given the weight savings. There’s entirely too much load on our soldiers already. It may interest the reader to note that the ESAPI plates were deployed in Iraq to combat fragments from IEDs, so perhaps the traditional kevlar-type soft armor fragmentation protection is insufficient. It is important to understand the expected threat level.

Further weight savings might be obtainable with a different choice of plates. ESAPI plates (and the SAPI plates they were derived from) were intended to be worn over soft armor, and the soft armor backers are required to get the designed level of protection from the plates. We’ll look at some alternative plates in the near future.

M230 LF Autocannon

Autocannons are awesome. Earlier, I talked about the ASP-30, an autocannon for light vehicle applications that fired the 30×113 mm round. This gives an explosive payload like a 40 mm grenade, but has a nice flat trajectory. It’s also currently the ammo of choice for the gun on the excellent Apache attack helicopter. While I love looking at old projects, we might consider if there’s another way to get similar capability without all the R&D costs.

Enter the M230 LF. Orbital ATK’s M230 is the gun used on the Apache helicopter. It’s externally powered and it uses a linkless feed, which is light and convenient for aerial applications. It’s less than ideal for vehicles though. The M230 LF has a longer barrel and is adapted for a linked feed. It’s still externally driven, using ground-vehicle-convenient 24V DC electrical power, and has a reduced rate of fire.

In terms of vehicle mounts, light turrets, and the increasingly popular remote weapons station, the M230 LF has a lot to offer over the standard Mk. 19 automatic grenade launcher or M2 heavy machine gun. Just like the ASP-30, it’s got a much flatter trajectory than the Mk. 19, giving it increased range and improved precision. Having an explosive payload gives it improved lethality over the .50 BMG round. The M230 LF has better range than the M2. Also, it’s externally powered, so it doesn’t need solenoids to cock it or work the trigger. It also improves on the ASP-30 by being a system that’s already in the inventory, so spare parts are already present.

Awesome. However, the M230 LF is not a perfect replacement for the M2 and the Mk. 19. It is not ideal for man-portable operations. It isn’t really designed to be broken down into smaller loads like the M2, and it weighs about twice as much. It’s not compatible with existing tripods, and the external drive functionality that made it so well adapted to turret use is problematic for infantry operations. You can’t have everything.

I am happy to report that sensible people are deploying the M230 LF on shipboard remote weapons stations and on vehicles. Oshkosh has even put some on their JLTV-winning design.

Namer IFV

I love the Israeli Namer. It’s great. Like Steven Segal, it is Hard To Kill. Its armor is proven effective against the most modern ATGMs. And it can carry a full squad.

But nothing’s perfect. The obvious limitation of the Namer was its firepower. Out of the factory, it came with a remote weapons station with an M2 heavy machine gun. So while it could carry infantry through eight kinds of hell, it couldn’t engage other armored vehicles or provide as much supporting fire as other mechanized infantry vehicles.

Until now.

Those magnificent bastards have done it. They’ve made an IFV version of the Namer. Now with a brand new, unmanned turret! Let’s take a closer look.

Primary armament is a 30 mm Mk. 44 autocannon. The classic Bushmaster II. This is a fine choice, and pretty standard. It’s got 400 ready rounds in a dual-feed system. Unfortunately, I have no information on how the 400 rounds are split up. 30 mm allows the possibility of airburst rounds, and gives a nice volume of stowed ammo. It’s a solid choice on the ammo vs. round size spectrum.

Coaxial armament is a 7.62×51 mm machine gun, with 700 ready rounds. Pretty good capacity, standard choice of armament here.

The turret also contains a pop-up missile launcher. This comprises two tubes for Spike ATGMs. I’m not sure which Spike version is carried, probably -MR or possibly LR. Spike is an excellent modern ATGM that’s similar to Javelin.

But wait, there’s more! The turret also comes with a 60 mm mortar. I haven’t been able to find the capacity for it. The Israelis love mortars, as I do. Their tanks have been equipped with mortars since the Centurion days, when they were retrofitted. This gives their IFVs some indirect fire capability, and anything that gets more mortars (and more firepower) to the troops is fine with me.

The nature of unmanned turrets, and the newness of this model, makes it hard to determine the amount of passive protection. I’d guess from the shape and bulk that it’s got autocannon protection (STANAG level 6), but that’s purely speculation. However, we can clearly see that the turret is equipped with radar and effectors for the Trophy active protection system. There are also the usual smoke grenade launchers at the front.

Sensors are also pretty standard, though details are scarce. There’s an optics array for the gunner, and a separate, independently-rotated unit for the commander. I’d expect laser rangefinders and thermal viewers for both, but I don’t have data on the generation of the thermal units, magnification levels available, or the laser type for the rangefinders. I’d also expect computerized fire control systems, but the details aren’t available yet.

This is actually pretty close to my ideal IFV sketch. I love it. I’d buy in a heartbeat. As should the US Army. A large number of Namers are built at the General Dynamics Land Systems factory in Lima, Ohio. There’s no reason why the GCV couldn’t have looked much like this, and there’s no good reason why this shouldn’t be bought in lieu of the failed GCV.

It looks like Hanukkah has come early this year.