RE:FPV this is one of those things that makes sense conceptually but is applicable less often in reality. There's a number of disclaimers here: * If the weapon model will ever be seen in third person view, mirroring is often not appropriate, as mirroring artifacts (flipped text and such) will be visible from certain…
To NOT use overlapping uvs on geometry of the same mesh that you will never see simultaneously is just nonsensical and a complete waste of valuable texture space, and even if you can in the case of small details like nurnies you bet I'll be stacking them. Think of the example of an FPS weapon. The very nature of the…