It's a good concept, but playing is really hard, there are many enemies at the start already so you have to shoot a lot of bullets, and if you miss your target the game is too punishing, as your bullet will keep looping until it hits something wether it it is you or someone else. It is a fun idea though.
I could suggest for eventual future updates to reduce the number of spawning enemies at the start and slow down the circle's closure at least at the start.