Why not try using a mask with gradient, usually I use that to create walls and stuff for SCI-FI. So let’s say you have a gradient from left to right, so the gun’s UVs should be placed in the correct order from left to right, plus add +1 to emission that it looks like the gun is spawned with nanotech or something like that.
So let’s say use this dissolve tutorial Unreal engine | Dissolve materials tutorial - YouTube but add order to mesh UVs and use gradient mask instead of noise mask.