Is a hand pump enough or do I need a compressor?

A hand pump is enough for light shooters, especially on small-reservoir guns, where 30 to 80 pumps tops the gun off after a session.

It is labor-intensive once a tank is empty (several hundred pumps from zero) and can introduce moisture if you do not drain the pump's water trap. If you shoot a lot, run a high-volume gun, or fill big bottles, a compressor or scuba tank quickly becomes worth the money.