[quote=@Dannyrulx]
Idea: My character has an Adeptus Astartes-issue bolt pistol that (s)he uses like a rifle.

Yes, it is somewhat canon that Astartes bolt pistols are like freakin' rifles to regular humans.
[/quote]

Aren't Astartes guns DNA coded to their genetically enhanced owners? They also have a kick not so much like a mule as much as a industrial pneumatic ram. I think it might rip an ordinary arm right off.