If you are looking for feedback, looks like your UVs need some work. I can see some warping in the texture that would probably come from bad unwrapping. For the texture itself, don't get comfortable with auto masks or just placing a texture on it and calling it a day. Manually adding details makes any prop shine. Think of where the gun would have more wear and paint it there, same with dirt etc. Parts of the texture that are difficult to make can also be done via geometry. Baking is a godsent.
The model itself looks good, keep it up