That's a shame. But as far as non-standard equipment are concerned, the Ultramarine Super Bolter has THREE firing modes AND the accurate quality. It's so disgustingly beautiful an Ultramarine Tactical can become the team heavy or the team sniper impromptu. I forgot where it was. I think it was on the First Founding book.
Well, Rogue Trader's MUI Weapon Interface says you can attack with the weapon as a free action. If you attach something to your armor and now doesn't attack as a half-action, you can full auto twice. Personally, I used it with a cheap las-variant with full auto (Because Lasguns don't have recoil) and suppression fire every turn as you stab them to bits.