i actually just got doing a high poly fn scar myself. at first glance this isn't bad at all. nice work! a couple crits if i may tho..
it seems like alot of your sub div corners/edges are very tight. if your going for a bake you need to smoothen them out prob by 2 or so. but with that said, the nozzle (where the bullet comes out) seems off to me. the tips are way to skinny, try working with that a little more. the grips extrusions are going to be more rounded, not so square. and you also have some weird smoothing errors that need to be fixed. but for the most part tho i like it! keep it up, il be watching to see how the bake turns out