Nice concept! There's potential here, though it still feels quite undercooked. That said, it's already a fun and functional game, great job!
Feedback:
- The art & colours are all a bit muddy, not really popping and bringing the scene to life, especially with the camera angle where it is!
- Personally, I would cut the reload physics challenge and just make it a set increment per bullet loaded. I reckon the player could enter a nice flow state with this change. For special bullets, you could assigned them to different reload keys and load them at the back of the queue, so the player needs to think ahead a bit for when the special ammo will fire in the sequence.