I think the animation is a lot like the shading, way too smooth in its transition of states. Theres low constrast in the shading, you could get away with way less shades of the the colours you are using. For instance you probably only need 2 reds.
You animation is similar, its very uniform in transition. The key frames could be a lot better broken up. The recoil doesn't seem sudden or realistic, the character is being pushed back gradually and gently. Anyways, it doesn't look too bad. The gun and the tilting of the gun looks ok, and thats my 2 cents.
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