I tried enveloping it before but all it does is stretch my geometry

By default, enveloping will blend a vertice between the two closest bones, so that each have an effect over it (hence the stretching). Because you’re doing a gun which is made out of solid pieces, you’ll want to go in and make sure that only 1 deformer is influencing a vert at any time.

After enveloping, select all the verts you want to be controlled by the animated null/bone, chose [B]Envelope[/B][COLOR=white]>[B]Reassign Locally[/B][/COLOR], and choose the animated null. Select the rest of the verts, do the same but chose the static null.

yep..

in theory, your unreal wepon should be envelope according to what parts move, rotate, etc.

In your weapon, i see two nulls..so it leads me to conclude that you have “root” and “nuzzle” which in unreal nuzzle is where the projects shoot from.

So really, all u gotta do is set an envelope using ONLY the root null ( the one on the handle) when u move, rotate and what not that should move with it.

The other thing is that for the nuzzle bone to follow you must parent it underneath the root.  That is as easy as draging and dropping the nuzzle null into the root null in the explorer.

Don’t know if it will, But this may help :

http://www.veoh.com/videos/v70672209GqQzcNK

Good Luck.