I modelled, UVed, and textured a SAR 21 assault rifle! Searching for references was tough, because this is not a widely-used or widely-known weapon. I used Maya, Substance Painter and Marmoset Toolbag.
Main shot.
3Q 1st shot.
3Q 2nd shot.
Back view.
Back view 2.
Wireframe.
Behind the scenes 1.
Behind the scenes 2.