Here’s the problem: it’s got a 4-round magazine. Given the size of the magazines, you can fit about four of them on your body before you take up all the available space, so you’re carrying 20 rounds ready … maybe another 20 rounds in a spare bandolier on your back if you’re willing to take the weight.

How many of thosse 20 ready HE rounds, which are highly lethal but absolutely no good at close range (except as slugs) are you willing to give up for shot-shell? Particularly when you get into an urban environment … close range target pops up — do you have time to change magazines, clear the HE round that’s chambered, and fire a 25mm shot shell?

So you’re probably still carrying a carbine for self-defense … so you’ve got a standard rifleman with all his load (body armor, SAPI, water, ammo, etc) plus a 14-lb (being generous) 25mm launcher and another 15 lbs of 25mm ammo. Ends up being heavier than the current M203 gunner’s load. It’s more effective under some conditions (like when all your HE targets are in windows more than 200m away), but it’s still problematic. There’s a reason the Army walked away from dedicated grenadiers (though the USMC has headed back that way with the M32 six-shot 40mm launcher, though you’ll see M32 gunners still carrying an M16A4, and the Marines do have a thrid fire team in their squads …).

What is on his head, and why is he wearing it in this crowd? And it looks like he’s got a couple packs of cards or something sticking out of it. I’ve never seen anything quite like that.

Anybody have any ideas what that contraption is?

The grenadier could defend himself with dumb shotgun rounds or a submachine gun and break out the high-tech ammo when his unit starts to fire and maneuver. The M79 was used that way in Vietnam.

The 5.56 weapon can’t be a bullpup — the 20mm portion is, and that mag takes up the rear space (unless you go side-by-side, which was one of the original OICW options but was eliminated going into final design downselect). Note that dude’s right hand is holding the 20mm magazine.

The sight’s so big because if it’s designed like the XM104 OICW sight, it has a direct-view optic (wide field of view glass is big/heavy) plus thermal sight, plus LRF, plus ballistic computer, plus power supply. The XM104 sight has gotten smaller, but it’s still pretty bulky compared to a plain-jane optic, or even a light thermal weapons sight. If they ditched the direct-view optic and went strictly electronic it would get a lot smaller, but then the folks would complain about not having a sight when the power fails (counter — a piece of glass without powered reticle is just a piece of class, anyway).

Looks like the Koreans got smart and went single-shot with the 20mm … the recoil mech for semi fire took up a lot of space/weight claim in OICW and is still a challenge for XM25. It also looks like they didn’t go modular with the KE and HE portions of the weapon, which will make for better integration and lighter weight.

The direty secret, though, is that the hard part of the whole system isn’t the weapon — it’s the 20mm warhead and fuze electronics. 20mm is a damnned small package to put programmable electronics, a power supply, enuogh warhead to matter, and still have it fly right … which is a huge part of the reason OICW ended up switching to 25mm before it was “restructured”.

I swear, though, the first manufacturer to successfully pull off an effective combinatorial weapon will have the world beat a path to their door.