Hooooo-kay.
Here's the deal. I'm a former Gunners Mate. And my specialty was the Mk 45 5"/54 Caliburs Light Weight Gun Mount. (Light weight how so, you ask? Much lighter than the old Mk42 gun, which had crew placements for both surface and air targeting systems. Yes, one for each because back then surface targets and air targets required instrumentation that was mutually exclusive to each other.)
And very often us shipboard gunners are part of boarding teams and protection forces because we are that familiar with the weapons we use. In fact, while I was stationed over in Japan, I was once tasked with guarding the small arms ammo to be used for our regular gun qualifications for the crew. This was a Big Fucking Deal because that meant I was to carry a loaded gun in a country where not even some of the police carry guns, and it was a LONG bus ride from Yokusuka to Atsugi, where the firing range was located.
That said...
Let me assure you, when you start talking HE, you're usually talking about good old RDX in one form or another (most of the newer compounds are actually mixtures of RDX with some form of energetic plasticizer). And that shit is not subtle. Stable, yes. Subtle? Hell nah.
Now, granted, it is used quite often in grenades. But you know how small those are. And I'm getting the impression that what you're after is something more like an M18A1 Claymore tripwire mine (which uses C4, which is, again, a compound of RDX with a plasticizer - yes, that shit is EVERYWHERE).
Now, here's the thing. Something like the M18A1? That will do the trick. The lethal area is suitable for clearing large rooms, and the fragmentation is soft steel balls, about the same as rounds from .22 rimfire cartridges. So there won't be much in the way of wall penetration. At least, not the walls in this place. But the problem lay in that these things take time to set up. Why? Because with that much ka-boom, you definitely do not want the ka-boom to come at you instead of your intended target. (Hence why Claymores use a shaped charge to direct the blast in a very specific direction - that being the infamous "Front Toward Enemy" that is practically a trademark of the Claymore mine.)
And the operation that's being run here is purely a smash-and-grab. While they're not taking any prisoners, they're also not inclined to stick around and clean house. Down that path, they start to stack the odds against themselves, increasing the chances that one of them will become a casualty.
Besides, they already "ventilated" their Boss. That was the guy that had that moment of slow thinking where they were all, "What? A floating gun!?" So it's not likely that this particular group is gonna be a problem to anyone anymore.
The real concern is how much exception will Space Dwerger's competitor - the ones who hired this bunch of thugs in the first place - will take to this turn of events. Are they gonna realize that they just messed with "That Guy You Do Not Fuck With" and ease off? (Because he actually does have a reputation already, which is part of why Space Dwerger so desperately wanted him to test out their prototypes while working on his order.) Or are they gonna double-down on the stupid and try something even more brazen?
