Sci Fi Assault Rifle

Hello. I created this game ready model to get better at texturing and I would like to know your opinion :)
Altering Design, HP, LP, UVs, Baking, Texturing by me. Thanks for all the feedback that helped me get this here ^^
Design of weapon was created by Pengzhen Zhang and I changed it slightly by adding some things:
https://www.artstation.com/artwork/LQlkR
Design of collimator was created by Thomas A. Szakolczay:
https://www.artstation.com/artwork/xwWnr