/ic/ - Artwork/Critique

I think there's some kind of chemical runoff contaminating my well or something, because I've been struck with a very strong, yet inexplicable desire to learn how to draw furry art. I've enjoyed sketching for many years, but my rendering and coloring skills are garbage and I've never done any digital art before now.

Here's my first project that it looks like I'm actually going to finish. I'm really pleased with how the linework turned out, but I'm really struggling with the shading. Shading the face in particular is giving me a lot of trouble. I'm also having some difficulty with drawing glossy metal. I'm mostly satisfied with the receiver/dust cover area, but the barrel and gas tube area still looks off.

I also need to add more floofyness. The tail in particular looks too solid.

Any criticism/ideas are a huge help!