In Hammer of the Emperor, on the table for designing pros/cons of variants for ranged weapons, there is an option to have "Crippling Munitions" granting the weapon Crippling (2). Now-- say I wanted to put that quality on a las weapon... kinda hard to cripple something with Pen 0.
So really I'm just getting ideas for how to justify a las (specifically a rifle, if that factors in at all) have a "cripple" effect.
Anything short of tech-heresy is fine by me.