The deployable weapons from 40k are formidable, but I'm not sure they fit XCF.
this is actually what I thought the heavy tu cost of miniguns was trying to simulate (at least in Fmp, I assume they're the same in xcf). there's no way a regular human can shoot one without a tripod of some sort, so you would have to pick up a tripod and redeploy it everytime you moved if you wanted to have any hope of aiming the thing.
so the deploy-able weapon thing makes total sense to me for miniguns and hmgs.
No, gyrojet is gyrojet, recoilles rifle is recoilless rifle, absolutely different.
Gyrojet slug does not have casing, it acts like a micro missle, meaning its launched not by powder combustion in casing, but by burning solid fuel inside itself and accelerating all the way to target untill it hits or runs out of fuel. (still maintains a lot of kinetic power after fuel is spent)
You can look up on youtube for gyrojet pistol shooting live video.
I think the point solarius is trying to make is, what additional gameplay element would such a weapon add over a recoilless rifle? both are basically just more accurate versions of human weapons. any other differences would be hard to simulate on the battlescape, regardless of how major they are in real life. I guess maybe the weight difference could work, but that doesn't seem worthy of a whole other tech tree to me at least.