It's an interesting concept and the game looks good, with polished animations and effects.
When it comes to the reloading mechanic, I would maybe but the barrel in the corner of the screen when reloading so the view of the enemies is not obscured.
Also, at the moment, reloading the barrel manually feels a bit like a chore. because I don't get any reward for doing so. Maybe certain combinations could unlock something (for example, only loading every other chamber would temporarily give you poison bullets, or loading all the chambers in one go without missing one would give you better bullets that kill enemies in 2 hits instead of 3).
Over all, a cool game.