Awesome entry! Pixel art is really good, the white outline is a nice touch... also the music is cool and the reload feats the theme pretty well.
The only thing is that the movement feels too fast for me, I think I would've enjoyed it and controlled it better if it was a little bit slower.
Last, you should add controller support! I've set it up using Joy2Key and it was so much better... I've mapped JIKL keys to the Right Joystick and the reload was much more fun!