With Level IV armor rising in availability, calls for “overmatch”, and the increased presence of urban warfare, will designers be able to meet the requirements for future small arms? Forumgoer Poliorcetes raised this question in a discussion at the Military Guns & Ammunition forum:

Now we are in a potentially difficult situation. On the one hand, it is allegedly demanded an overmatch capability, and for sure state of the art sights and near-future sights demands a more energetic cartridge. On the other hand, we will need to surpass reliably Level IV armors.

Luckily, Russians and Chinese have the same problems as us. BUT as you know their RoE are more relaxed and ESAPI or XSAPI are less of a problem against company organic resources.

Anyhow, NATO armies are going to demand reliable cartridges against, say, ESAPI before 2030. Besides, I guess that they are not going to renounce quickly that rapid fire semiauto capability so common from 60s onwards. Therefore, they need to maintain weight under control, rapid fire capability and well managed recoil of a rifle that, at least, needs to fire a 3,300-3,500 J non-tungsten based bullet. Old and known design elements are not going to be longer valid at least in their actual balance, and if CT is adopted, a lot of them will need to be reinvented.

I’ll set aside talk about small arms engineers and whether they are up to the task for another day. For now, I’d like to address the state of things, and how they might change moving forward.

First, it’s no secret that I think “overmatch” is a red herring. In Vietnam, the US had an “overmatch” round, emphasis on traditional marksmanship skills, and low soldier individual load, and it wasn’t an advantage then. I am also not sure that optics do demand a more energetic round, as poliorcetes suggests. I can see the argument there, certainly (it goes: optics let you shoot further, 5.56mm wasn’t designed to shoot that far, ergo a more powerful longer ranged round is needed to match the optics), but I can think of other plausible outcomes, too. For example, optics may not allow substantially longer engagement ranges than previously assumed*, but they may allow better precision which makes smaller rounds more effective than they otherwise would be (closer misses = better suppression, more hits on critical body structures = better lethality, etc). So I think there’s a discussion to be had about whether optics will necessitate larger ammunition, but definitely not any certainty that they will.

*For the combined reasons that, beyond about 300 meters, hitting a target is about more than just seeing it, and that previously assumed engagement ranges are often several times further than what troops have realistically been capable of. Many assume that optics will take the effective range of riflemen from 300-500m (previously assumed) to 600-1000m, yet it seems much more likely that optics will instead bring their effective range closer to what was previously assumed. In other words, a modern rifleman is probably only effective to some 100-200 meters, and the addition of an advanced magnified optic may raise that to 300-400 meters – in line with the previous expectations.

Also, the ability to penetrate Level IV armor may be too much to demand from an individual weapon, or it may come with costs too high to be practical. It’s pretty easy to imagine that a Level IV defeating round would be so large that it is actually counterproductive as a standard issue individual weapon round. After all, if you can defeat Level IV, then you have effectively obsolesced it – and now you’re back to “he who carries the most ammo wins”, and with such a heavy round, you’d be losing badly at that contest. I also think the nations that can solve the Level IV armor problem without changing their arrangement infrastructure too much will come out ahead, especially if Level IV is actually made obsolete at some point (which I think is unlikely, but its importance might decrease). So the right solution here, or at least the most immediate and seamless one, seems to be to use (possibly with modifications) existing assets to defeat armored troops. The possibility I’ve pointed to in the past is 40mm grenades, which bypass armor. If we look at the last time armor became so effective that it obsolesced existing weapons (which was about the 1300s AD), we saw a few things happen: 1. Weapons that were ineffective against armor continued to be used since armor was expensive and difficult to wear all the time. 2. Non-standard weapons that did not penetrate armor but could bypass it became much more popular (e.g., maces, rondels). 3. Engagement distances against enemies wearing armor became much shorter – often, grappling-distance was required to make a solid hit with a mace or penetrate a weak spot with a rondel. 4. Entities that could afford armor enjoyed substantial and lasting advantages against those that couldn’t.

So my expectation is that long range armor penetrator efforts will not result in a practical solution for the individual weapon, and overall effective ranges for small arms will be reduced when engaging enemies with Level IV armor. I expect the <200m combat phase to be the critical phase for small arms against armored enemies, as that’s where underbarrel grenade launchers and targeted fire vs weak points will be most effective. This suggests that one solution might be to eliminate the specialized grenadier’s position, and instead issue to all riflemen underbarrel grenade launchers as standard accessories. This could mean the bullpup configuration, which is rear-balanced, might become more desirable, but it is also likely that this would drive lighter and lighter UBGL designs (e.g., the Beretta GLX-160, which is some 50% lighter than competing UBGLs) which might make that configuration unnecessary.