Gun from a concept

A gun model created from a concept, although this could very easily be turned into a game ready asset I currently am using a 4k map for the base and scope, while the underbarrel and barrel attachment use 2k maps. This is my first time trying out a new method and there is some beveling issues. The detail and bevels are baked down from a pass in zbrush

The concept:
https://www.artstation.com/artwork/oJ60q