Tag Archives: militariana

On the XM913 50mm autocannon

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With a public, successful test firing, now is a good time to talk about the XM913 50mm autocannon, a modern application of the 50mm Supershot (sort of). The rounds are the same overall dimensions as the 50mm Supershot rounds, i.e. a straight-walled version of the 35x228mm cartridge. Since it’s building on an existing cartridge, the XM913 is actually a rather boring gun. It’s just a Bushmaster III with a different barrel. Same feed system, same great electrically-driven “chain-gun” design. The Bushmaster design has proven to be very reliable and scalable, since it’s externally-powered action doesn’t have to be recalibrated to function correctly with a different amount of recoil or gas. Rate of fire is also easy to adjust.

The ammunition in question is rather more interesting. While it has the same overall cartridge dimensions as 50mm Supershot, the new case is 100 mm shorter, at 230mm length instead of 330. Where 50mm Supershot was designed to give more KE power for armor penetration, the new rounds are designed to launch a larger volume projectile, for better airburst and guided options. Current design is for a command-guided airburst round for C-RAM and anti-UAV work. And it should still work with the previous rounds, if more armor penetration is desired.

Ammunition is the same base diameter and overall length as 35x228mm, so we’d expect the same ammunition capacity. It’s about half what you can get with 30x173mm, give or take depending on details.

On to what we think. I’ve always liked the notion of 50mm Supershot. I’m pretty skeptical of some sort of command-guided C-RAM munition, but bigger airburst is better airburst. We’ll see how tests shake out.

2019 Self-Propelled Artillery Revisit

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Last time on Parvusimperator Picks a Self-Propelled Howitzer for Borgundy, I ended up going with the big, expensive Panzerhaubitze (PzH) 2000. I also eliminated wheeled vehicles out of the gate for concerns about capacity. Since it’s been a while since I’ve talked much about the Queen of Battle, I thought I’d revisit my procurement decision, because that’s loads of fun to write about and tend to be popular with you, dear reader. While available systems have not changed, let’s open the floor up. We will require protection for gunnery crews while firing, to simplify this a little1. So let’s dig in.

First, I’m going to relax my tracked-vs-wheeled constraint. This is artillery. It’s a support vehicle. With the range of modern systems, it’s not critical that the system be a perfect match for tanks and IFVs. Also, trucks should have no trouble getting to wherever a wheeled system is. What is important is 155mm caliber, an L52 gun, and a careful look at how we might plan to use the system. Wheeled systems have advantages in lower maintenance costs, better mobility via roads, and generally better strategic mobility if you care.

Somewhat-recent events in the Donbas reminded us that artillery is a very effective killer, and that a reasonably sophisticated opponent will endeavor to use counterbattery radars to locate and destroy one’s own artillery. So we’re thinking hard about shoot-and-scoot. Let’s get on to some plausible contenders.

As before, we have the German PzH 2000. It’s well protected, tracked, and has an excellent capacity of 60 projectiles plus charges. It has a five round MRSI capability. On the downside, it’s expensive and the heaviest at 56 tonnes. Once its empty, it has to be reloaded in the usual, manual way.

We also have the Korean K9 Thunder. It’s tracked, with a capacity of 48 projectiles plus charges. It has a three round MRSI capability. It also is the only one available with an armored resupply vehicle, the K10. The K9 weighs about 47 tonnes. In its favor are the fact that the South Koreans are buying tons of these, and they have a nice upgrade roadmap. The currently available K9A1 improves the electronics and navigation systems over the previous model, and is the current standard if one was buying today. Samsung Techwin is also working on an A2 version with fully automated shell and propellant handling and a reduced crew. It should also feature an increased rate of fire.

There’s also the Swedish Archer system, which has a low capacity of 21 rounds, but has a very high degree of automation. Like the ill-fated Crusader, it has entirely automated handling of artillery rounds, propellant charge modules, fuse-setting, and primers. As a result, it has a best-available six-round MRSI capability. Weight is somewhere in the middle at 33 tonnes. It was supposed to have a resupply vehicle, but that got axed.

Finally, we have the Boxer RCH, which takes much of the gun from the PzH 2000 and mounts it in a fully automated turret on the back of a Boxer MRAV. It has low manning, but not much is available about it, because no one has bought any. This is one of many mountings of the Artillery Gun Module on various chassis, and the same system has also been mounted on an ASCOD 2 chassis.

We also have Denel’s G6, which saw combat in the border with Angola, and has been kept up to date by the scions of Gerald Bull’s Space Research Corporation. It’s a somewhat large wheeled vehicle, and builds on South African experience in making mine-resistant platforms. Current versions have improved fire control and ammunition handling, and are equipped with an L52 gun that has a chamber with 23L (JBMOU-compliant2) or 25L capacity. These are the G6-52 and G6-52L versions, respectively.

We have contenders. Let’s look at some salient characteristics in a chart. Note reloading rates, instead of time to completely reload. MRSI are the maximum number of rounds possible according to the manufacturer. Bursts are 3 rounds, as fast as I could find the manufacturer claiming they could shoot them.

SystemWeight (tonnes)CapacityMRSIburst (sec)Reload Rate (shells/min)
PzH 20005760595
K9A1 Thunder474831512
FH08 Archer33216202.5
Boxer RCH38.53059?
G6-52(L)46475 (52) or 6 (52L)154.7

On to some commentary. Archer was supposed to be a joint Swedish-Norwegian project, but the Norwegians pulled out. Digging through old defense magazine articles, Norwegian concerns were the low capacity with lack of automated resupply system, issues with too large a dispersion, and too high ground pressure. Archer has seen no export success, and seems to be expensive.

Recently, K9 has been seeing quite a bit of export success in Europe due to its very reasonable cost and favorable licensing terms, which is notably less than that of Panzerhaubitze 2000. It also beat the Mista-S in an Indian tender. Other export users include Norway, Finland, Estonia, Poland, and Turkey.

Despite the higher cost, Panzerhaubitze 2000 has also seen plenty of export success with other NATO members as well as Qatar. It also has an armor kit designed to protect it against DPICM-type submunitions that you might find in a counterbattery rocket artillery salvo, especially if your opponent is Russia.

And the Boxer RCH hasn’t been bought by anyone yet. Rumor has it that it’s the favorite with UK MoD in their upcoming procurement contest. That said, it’s quite heavy for a Boxer variant, and it needs a different engine.

Denel has a long history of working on long range V-LAP rounds, and the G6 can take advantage of this. The G6-52L can use its non-JBMOU chamber to fire the M9703 base-bleed/rocket-assisted EFRB VLAP projectile a distance of 73 km in tests. Which is best in class by far. Otherwise it’s a pretty solid option with good but not great capacity for ammunition.

At this point, I’m strongly considering the G6-52L. At least until we consider some other things. First, Denel’s own (old) marketing materials basically dropped the 25-liter chamber version, focusing on the version that is JBMOU compliant with JBMOU compliant ammunition. The G6-52 itself hasn’t been exported anywhere: Denel’s last export order was the regular G6 to Oman in the late 90s.

Also, all of the present ammunition development work is being done to getting more range out of a JBMOU-compliant gun system. So the range limitation of the other guns isn’t likely to last, and we’re not likely to see more good testing on the -52L version. As a result, I can’t go with it. Regrettably.

We’ve now come back to the choice I had last time, and my answer is the same. I prefer the better fire rate and submunition protection of the PzH 2000. Things to keep an eye on would be an aggressive price move from Samsung, or the rumored K9A2, which is supposed to include fully automated ammunition handling and reduced crew. If that keeps the reasonable stock of ammo, we’d prefer it, especially since it might also improve the rate of fire.

Let’s also take a brief moment to talk about the usual 800 lbs. gorilla in the room: the US Army. Having had a few M109 replacement programs terminated, they’re being quite a bit more conservative this time with a two-stage approach. The first stage, which has just entered production is the M109A7 upgrade, which replaces the M109’s powertrain with that of the M2 Bradley, and upgrades the suspension to handle more weight. Gun upgrades, as well as an automated ammunition loading system, are coming as part of the second stage. The gun is supposed to have an L58 barrel, so it should be pretty fun. For now, there’s not much worth looking at, unless one uses or plans to full-fleet Bradleys. It’ll probably be interesting to look at in the future, however.

  1. So we’re going to ignore for now all of the nifty “towed howitzer replacements” like CAESAR. Those are super simple though, and ought to be mounted to a common truck. ↩
  2. Joint Ballistic Memorandum of Understanding, an agreement to standardize ammunition and propellant charges for the Next Generation of NATO artillery. ↩

On 40mm Grenade Launchers

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The evolution of western 40mm grenade launchers is a bit of a back-and-forth affair. Initially, we had the M79, which is a single barrel, break-action weapon with its own wooden stock. Sort of an old shotgun given a huge dose of steroids. It was proven super effective in Vietnam, launching a very reasonable amount of high explosives with a minimum of setup. Of course there were drawbacks, especially due to the low rate of fire and limited amount of rounds that could be carried.

The first approach to fix this was called the “China Lake Grenade Launcher.” Taking yet more cues from shotguns, this was a pump-action grenade launcher, with a three-shot magazine for the fat 40mm rounds. Where the M79 weighed about 6 lbs empty and 6.5 lbs loaded, the China Lake launcher weighed 8.2 lbs empty and about 10.2 lbs loaded. Usage was mostly confined to Navy SEALs, who were generally fond of the weapon. The US Army was focused on its SPIW program, which would end up going nowhere. Unfortunately, that meant that the sensible China Lake launcher also went nowhere.

The other approach was the cheap and cheerful M203, an underbarrel launcher that attached to the rifleman’s M16. It’s much lighter at 3 lbs, but has a shorter effective range and makes the rifle a bit awkward to use. Also, the sights aren’t integral with the M203, which leads to more opportunities to lose or screw up a zero. Some standalone launchers were made starting in the 90s, but they never achieved much in the way of widespread use. The original M203 attaches to an M16A1 or M4 by means of a pair of barrel brackets. Some newer variations can be attached to picatinny rails instead.

Replacements to the M203 have been concerned with fixing some of its less than desirable traits, chief among them the inability to use longer ammunition. The US Army’s replacement for the M203, the HK M3201 does this by means of a side-opening action. It also has an integrated grip to facilitate standalone usage, and has integral sights. These don’t have to be rezeroed if the launcher is moved between rifles or attached to the stock kit. However, the M320 is a bit heavier than the M203. The integrated pistol grip and included vertical folding foregrip seem to indicate that the M320 is optimized for standalone use.

The big competitor to the M320 is FN’s EGLM, which had an extension to move the trigger down where it could be fired from the rifle’s regular grip using the middle finger of the rifleman. Extensions are available for both 5.56 magazines and 7.62 NATO magazines. The EGLM can also accommodate longer rounds, but does not have integral sights. Also, like the M320, it has a double action trigger. This is marketed as giving second strike capability, but I really don’t think that’s all that important given that you aren’t using super old grenades.

So let’s get to picking. There are a bunch of other grenade launchers out there that are marketed in packages to go with various other service rifles, but that’s not a big deal to us M4 users in Borgundy. And when I go looking for fancy rounds that you can’t fit in an M203, I mostly get a bunch of “less-than-lethal” options2. Great if you’re the LAPD, but I don’t really see the utility for standard issue to the infantry. The other thing that you can load in the EGLM and the M320 is the Pike missile, which is a pretty cool laser guided mini missile with about 2,000 m of range. However, that’s quite a bit of reach for the regular grenadier in the rifle squad, given that the standard 40mm round has an effective range of about 400 m. Again, it seems kind of a niche weapon. Great for special forces. I’ve also mentioned that I’m not buying the second strike argument as anything anywhere close to necessary. The M79 and M203 don’t have that, and soldiers have been using those effectively in combat since the 1960s. And at the end of the day, the venerable M203, even with the picatinny rail adapter, is going to be way cheaper than the competition.

So we’ll go with the M203A2 (or equivalent; the M203 is a widely licensed system), which has the picatinny rail attachments. We’d want to purchase the stock kits to go with these as well, since we’d expect3 these to be used more often in the standalone configuration as long as we can keep that configuration reasonably compact and light.

We should also talk about the the Milkor MGL (M32 in US Service), which is sort of like a successor to the China Lake Launcher idea, albeit from South Africa. It has a six-round, revolver-style magazine. Clearly, it’s trading weight for capacity. An M203 in standalone configuration weighs a bit less than 5 lbs unloaded, depending on options.4 The six-shot M32 weighs 15.4 lbs unloaded. And that revolver magazine makes for a pretty bulky gun. Anyway, I’m kind of skeptical of the M32, given that the grenadier is still likely to have to carry a carbine in addition to it. At least the rounds it fires actually work, unlike the XM25. I think it would be reasonable to procure some M32s, but I’m not really sure where to put them in the TO&E. Probably in the back of a vehicle somewhere.

And there you have it. Cheap and cheerful launchers for cheap and cheerful grenades. In terms of basis of issue, I think two per squad is a pretty reasonable choice.

  1. Under no circumstances should this be confused with the SIG P320 pistol, which is known in US Army service as the M17 pistol. ↩
  2. People also talk about medium velocity grenades, but I can’t seem to find anybody actually issuing any. Even the US Army. ↩
  3. I don’t have a ton of M203 experience either way, but the consensus at Primary & Secondary amongst those who have used them is that standalone grenade launchers are better. ↩
  4. LMT’s L2B weighs 4.7 lbs in standalone configuration. We can go lighter if we get their L2X with a 7″ barrel and its compact stock kit, which at 3.6 lbs all up is the lightest launcher I can find. ↩

On Light Machine Guns

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The US Army has decided that they might could replace the M249 with something. Possibly. Or maybe it’s just Lucy Van Pelt with her football. Anyway, the US Army claims it wants “Overmatch”. Or something.

Overmatch

The fear is, of course, Russians (or Chinese or whoever) with level IV-equivalent body armor. Let’s think about this for a minute. Level IV hard plates are rated to stop the .30-06 M2 AP round, which is a pretty darn good steel-core AP round. And no existing round short of .50 BMG is significantly better at penetrating armor than .30-06 M2 AP; it’s actually better at penetration than both Russian 7.62x54mmR B-32 API and 7.62x51mm M61. I’m not sure how a new 6.8 mm cased telescoped round is supposed to be massively better at armor penetration than .30-06 M2 AP, unless it’s supposed to use a tungsten core. Tungsten becomes problematic once you look at the cost and where most of the world’s tungsten is mined.

It could also be some sort of Magnum 6.8mm CT round with tons of velocity, but then managing recoil becomes a huge problem. After all, steel core .30-06 is not enough, so we need more energy. More energy means more recoil, because physics is a real jerk sometimes.

Let’s also recall my usual criticisms of some sort of radically new and unproven small arms technology, which is exactly polymer-cased telescoped ammo is. We’re talking about completely new ammunition manufacturing techniques, completely new cartridges, plus massive changes in how a firearm operates. We’ll let the US Army put up and prove the stuff or shut up. Come back and talk to us in five to seven years, and then we’ll know if it’s more than the next SPIW.

Okay, so that should deal with all the WONDERCALIBER advocates. Don’t trust Big Army to buy crazy new stuff. Wait for ambitious programs to come to a conclusion. Don’t be a beta tester. Wait for bugs to get worked out. And there will be bugs.

If we’re sticking with conventional calibers and known solutions, that makes our lives a lot easier. Let’s take a brief look at squads to see how we might use the LMG. I’ve been on record before that I don’t think squad size matters too much, and I still don’t. Picking the Namer as our (Heavy) IFV of choice lets me have a nice big dismount element of nine, which makes life easy. Nine men is a pretty classical dismounted infantry squad size. Squad leader, two fireteams of four men, and one LMG per fireteam. Two LMGs in the squad is a lot of firepower, and lets either team cover the other for fire and movement if desired.

Had we gone with a smaller, more conventional IFV with a dismount team of six or seven men, I would have copied the Australians and gone with two fireteams of three men each (plus a leader in the seven-man case) and kept the two LMGs per squad. Again, fire and movement. Also, it allows for better implementation of parapet foxholes.

And now, a brief word on command. In general we’d expect the IFV commander to be in overall command, and to remain in the vehicle when the troops get out. The vehicle commander would be senior to the dismount commander.

There is the pressing matter of caliber, configuration (i.e. mag fed or belt fed), and model. Let’s take those in order. Caliber is pretty easy. It should be our usual 5.56mm to maximize bullets per pound of loadout and (therefore) volume of fire capability. It’s also a lot easier to carry, since most GPMGs aren’t workable with a single gunner (i.e. without an assistant gunner).1

And we’re going belt-fed, because we want that big ammo reserve for suppression and sustained rates of fire. Large capacity drums are bulky, heavy, annoying, and generally unreliable. They also usually have to be stowed when empty. Screw that. Belts it is, by God and John Rambo!

Belt-fed 5.56mm light machine guns. They’re super fun to shoot. We just have to pick one. For the most part, they’re all pretty similar. The one that stands out weight-wise is Knight’s LAMG, which is significantly lighter than all the rest. Which should make it a slam dunk, except that no one else has bought them. And such a massive weight savings has me nervous, since there’s no such thing as a free lunch. I have some concerns about durability, and since no one has issued them on a wide scale, no one has worked the bugs out. Again, we don’t do beta tests. So we’ll pass too. Which basically leaves a whole bunch of equivalents in FN’s Minimi/M249, HK’s MG4, IWI’s Negev, and some others that I’m forgetting. They’re all pretty much the same, and I don’t think you can go wrong. Of course, this also means that there’s not much of a reason to switch, unless you wanted to beef up your local firearms industry. Since I hate wishy-washy conclusions, I’ll go with the proven M249, mostly because it’s the only one I have any time on. It’s also been licensed to a number of other countries.

I’m sure the Wondercaliber advocates are going to ask about body armor. Well, okay. Fine. Shoot them more. It’s a belt fed. Ceramic plates are only good for a few hits. Even the multihit rated ones. You have 200 rounds in the belt. Use ’em. Also, the real killer is and always has been high explosives. 40mm grenade launchers, rocket launchers, recoilless rifles, mortars, and especially artillery. More on that in a few days.

  1. I think this might be a change from the last time I wrote on squad support weapons. It happens. ↩

On Split Squads

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One of the things that has always confused me is why the US Army mechanized infantry platoon features split squads. It features four Bradleys and dismounts organized into three squads of nine men each. Since each Bradley holds six or seven dismounts, this means squads have to be split to be reconstituted later. While this matches light infantry practice, it always stuck me as needlessly complicated.

It wasn’t always this way. Originally, the Bradley and its six dismounts were considered as a “squad”, with the Bradley acting as a big, tracked, fire support unit. There were problems with the execution. The first was the question of squad leader. There is always the question of whether or not the squad leader should lead the dismount team or act as vehicle commander. The US Army said, BOTH! As a result, the Bradley commander would dismount along with everyone in the back. But this would lead to a suboptimal arrangement with the gunner having to perform double duty as the vehicle commander. So one of the dismount members would be cross-trained as vehicle commander, and he would climb up and take the place of the Squad Leader as vehicle commander.

That’s needlessly complicated, and for once the Army agreed. They decided that while they were in there revising the platoon org chart, they would work for more homogeneity. The Bradley Platoon of four Bradleys got rethought into two pairs. This mirrored U.S. Army thinking in the tank platoon, where four tanks were thought of as operating as two pairs of tanks. Each Bradley pair would get a squad of nine men to account for. Given that early Bradleys had six seats for dismounts, the Army split them into a fireteam of four per Bradley, and one of the two Bradleys in each pair got a (dismount) squad leader. Now, Bradley vehicle commanders could be just vehicle commanders, dismount squad leaders could be just dismount squad leaders, a dismounted squad could perform fire and maneuver on its own, and the dismounted squad was identical to the light infantry squad. The US Army has tended to like the idea that each infantry squad can be capable of fire and maneuver by itself. This also left six empty seats per platoon, which was sufficient for the platoon commander, XO, and any attached extras like radiotelephone operator or medic.

The next step to get us to today happened with revisions to the Bradley itself. A desire for more protection and the realization that the firing ports were useless led to them being plated over as part of the changes for the M2A2 version. Since the troops no longer needed to shoot out of gunports, the seats could be rearranged into more conventional benches along the sides of the vehicle, and the designers were able to squeeze in one more dismount, for a capacity of seven. Applying these to the previous organization chart meant that there were now ten empty seats, or room enough for another squad. This brings us to the platoon of four Bradleys and three dismount squads of nine men each that we know today. The careful reader will note that there is now no longer space for much of a command group or attached extras, but that’s something that the Army has not been bothered by.

Personally, I don’t like it. I’d much prefer to take the original concept of six (or seven) man dismount element and Bradley fighting vehicle as the squad, and skip the place-switching. That’s a lot simpler, removes the requirement of fireteams to “form up” to become squads, and would still allow for a bit of fire and maneuver on its own if we relax the desire to always have four-man fireteams. Australia is going exactly this way in their latest reorganization. I would also point out that while homogeneity is nice, different sorts of units have tended towards different organizations. No one is trying to organize a heavy weapons squad or platoon like the regular rifle squad or platoon over in light infantry-land.

Bradley Advanced Survivability Test Bed

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We’ve known that crew survivability can be enhanced by isolating crew from the ammo, and providing blow-out panels to direct any cook-offs away from the crew. These features are usually designed in from the beginning, as in the M1 Abrams or T-14. Let’s look at a test bed designed to add these features after the fact.

The M2 Bradley Fighting Vehicle and M3 Cavalry Fighting Vehicle carry an awful lot of ammunition, and aren’t super well protected. US Army studies indicated that an infantry carrier like the Bradley was likely to be targeted by anything on the battlefield, including the antitank weapons that it really wasn’t designed to resist. While explosive reactive armor could be added to supplement existing armor, this wouldn’t do very much against APFSDS rounds.

The Bradley Advanced Survivability Test Bed (ASTB) implemented a pretty extensive redesign of stowage. Most of the TOW missiles were moved to hull stowage racks outside of the crew compartment, with three missiles in an external compartment in addition to the two in the launcher. Two more were stored low on the floor of the crew compartment, although these could be replaced with Dragon missiles that were of more use to the dismounts. This limited amount of stowage in the crew compartment was intended to allow the vehicle to fight if the external stowage was not immediately accessible. Reserve 25mm ammunition was compartmentalized, with blow-off panels and separation for the rounds provided in the compartments. As a result, reserve ammunition capacity was reduced from 600 rounds in a regular M2 to 588 rounds in the ASTB.

Fuel was also mostly moved to large, external tanks at the back of the vehicle to prevent fires in the crew compartment. A 30 gallon “get home” reserve tank was provided internally.

The ASTB was also fitted with spall liners, additional applique armor, and protection for the sights. These features would get rolled into production models of the Bradley after live-fire testing of several models, including the ASTB, in 1987.

As for the rest of the features, I do not know why more were not adopted.

On the BMP

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Let’s talk about the BMP, specifically the BMP-1 and BMP-2. The BMP-1 was pretty revolutionary when it first appeared, and was extremely influential. Interestingly, the design requirements go back to the early 1960s, when Soviet Doctrine came to embrace tactical nuclear weapons and chemical weapons. This led to a desire for a vehicle that would be highly mobile and allow infantry to fight from inside in order to minimize exposure to the expected hostile battlefield environment. By 1967, Soviet interest in heavy use of tactical nuclear and chemical weapons had waned, but the design requirements were set (go figure).

The BMP-1 used the powertrain from the PT-76, came with amphibious capability, and provided NBC protection for the crew of three plus the eight dismountable infantry inside. The infantry were provided with NBC-sealed firing ports for their Kalashnikov assault rifles and machine guns, and had roof hatches to operate weapons with a backblast, like RPGs. These ports were arranged four per side and two aft. The turret of the BMP-1 had a 73mm smoothbore gun that fired the same projectiles as the standard infantry recoilless rifle, a coaxial machine gun, and a rail for Malyutka ATGMs. The turret distributed some platoon/company level support weapons down to the carrier vehicle. This turret was a one-man affair, as Soviet doctrine of the time had the commander dismount with the rest of the infantry in the back to lead them.

The BMP-1 had a number of notable shortcomings. The lack of armor is one, and the small size meant that any hit would strike important, flammable things. The commander-outside-the-turret arrangement made fire control difficult, and forced the gunner to work as an ersatz vehicle commander when the squad dismounted. Wartime experience in the 1973 Yom Kippur war was decidedly mixed. The Egyptians were satisfied with their BMP-1s, which were used to support missile-equipped antitank infantry teams. The Syrians used their BMP-1s in head-on attacks that left them to be smashed by Israeli antitank guns.

The effectiveness and widespread use of antitank missiles in the Yom Kippur War was also a problem, since even the most rudimentary missiles outranged the 73mm gun on the BMP-1. A quick response to suppress an antitank missile team (and screw up their command-guidance concentration) would also be hindered by the separation of commander and gunner. Hence, the BMP-2 received a two-man turret with a 30mm gun that had a much more reasonable trajectory.

San Antonio-class BMD Ship

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Ballistic Missile Defense is tricky. It requires lots of radar power and plenty of missiles. Right now, you can use your Aegis-equipped ships like the Arleigh Burke-class for the job. But those weren’t designed for the role, and the current state of the art SPY-6 radar is as big as you can fit on one. That is still not ideal for BMD work. Could we do better? Could we make a big air/missile defense ship, preferably on an existing, proven hull? Huntingon-Ingalls has some thoughts on the matter. They currently make the excellent San Antonio-class amphibious transport dock, and think it would be a great candidate for conversion. Let’s look at their proposal.

The San Antonio-class is a large, modern ship for amphibious operations. They are 684 feet long, 105 feet wide, and displace 25,300 tons. They have a large helipad aft for operating MV-22s and have a well deck to launch and recover landing craft or amphibious vehicles like the LCAC. They’re currently in production too. At present, armament is limited to two RIM-116 launchers and two 30mm cannons. They also have provision for a 16-cell Mk 41 suite, but are not fitted with those at present.

HII’s proposed conversion ditches the well deck and and sports a redesigned superstructure capable of mounting four 25’x35′ (WxH) S-Band AESA arrays for better search and discrimination of ballistic missile targets. Four X-Band Arrays would be fitted above the S-Band arrays for tracking and fire control. The large hull of the San Antonios allows the BMD variant to carry no fewer than 288 Mk. 41 launch tubes.

The large hull of the San Antonios allows for plenty of extra power generation and cooling equipment, so that won’t be a problem. The large hull also allows for a higher radar mount without compromising stability. One currently noteworthy limitation is that the San Antonio-class LPDs are only capable of about 22 knots. For the role it’s designed for, that’s not a huge limitation, but they’d slow a task force down if included in one. And the number of tubes would make them tempting to include in a task force.

Finally, let’s talk cost. To the good is that the San Antonio-class production line is hot. An existing hull is no small savings. On the down side, a fancy Aegis-type suite plus big radar that isn’t going to be cheap, and I know of no appropriately-sized radar offhand that would do the job. Radar development isn’t cheap. Overall, I’d say it’s a good idea if you’re really dedicated to BMD, but without actual price numbers, I can’t really give it a great thumbs up/thumbs down. My gut is that it’s a bit too expensive for what it is, given current budget priorities.

Deploying the 6.8 mm SPC 2 Cartridge

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The 6.8 mm SPC cartridge was designed to improve the firepower of US special operations forces without requiring the issuing of an entirely brand new rifle. It’s one of many alternative calibers for the AR-15. While it had the backing of Remington, and was designed with the help of some active special operations forces, a number of issues have come up to get in the way of its popularity. These include (in no particular order) two different SAAMI specifications for the cartridge, more effective 5.56 mm cartridges, ready availability of 7.62x51mm carbines, a whole bunch of other important gear that’s not going to pay for itself, and the round not being a non-NATO standard has mean that it hasn’t been adopted by the organizations that worked to develop it. However, a middle eastern special forces unit has adopted the weapon as a compact carbine. Let’s take a look.

This unit contracted with LWRC for the gun, with the goal of having a very short barrel (8.5″) and plenty of firepower. Given a relatively large order of more than 30,000 carbines, LWRC decided to make some changes. To ensure reliable feeding, they worked with Magpul to design 6.8-specific magazines. These are wider than standard AR-15 magazines, and the magwell on the new guns was widened to accept them. The new magazines have that same great windowed PMAG design, hold 30 rounds, and weigh 1.32 lbs fully loaded.

Other than the aforementioned 8.5″ barrel, the rifle has a quadrail handguard, pistol-length buffer tube, PDW-length stock, and a short-stroke gas piston system. The top rail of the handguard is removable to clean or service the gas piston. The rifle is the SIX8-UCIW. A version with a longer barrel, as well as an SBR version are available for civilian purchase, though obviously without select fire capability.

LWRC also worked with ATK (the parent company of Speer) to get a round that would function well in a rather short barrel. ATK obliged with a special round that will do the job, even with military flash suppressants. And yes, it’s SPC II spec.

Ok, what do we think? Well, it’s a solid execution of the “PDW” concept for a protective detail rather than for rear echelon troops. A short, relatively light package with plenty of firepower is exactly what this will deliver. I’m not a big fan of ‘nonstandard’ cartridges for general issue (who, admittedly are not expected to have super-short 8.5″ barrels), but I like the thought process here. Another tool in the toolbox, and one that fills a useful niche at that.