If you are going to Banteay Srei temple about 35 km from Siem Reap, about half-way there is a right turn to Siem Reap Shooting Gallery. Unfortunately I did not see any road sign, so you must rely on your taxi/tuk-tuk driver to show you the way.
There were not many visitors there, probably due to high cost of the bullets. On arrival, you are presented with a price list of bullets of various guns: Kalashnikov, Uzi, M-16, heavy machine gun, all the way to anti-aircraft gun. I chose M-16: USD 50 for 30 bullets, a rather-steep price. But hey, I come from a country where possession of firearms is strictly prohibited. Price doesn't really matter for a once-in-a-lifetime experience. Heavy machine guns' bullets would set you back much much more, up to USD 300 for a chain of bullets.
Among the light machine guns (Kalashnikov, Uzi, M-16) only the M-16 that can shoot in automatic mode, I think due to the condition of the guns.
The attendant (looked like a soldier) was a boring and bored guy, a cold personality with few words.
They did care about your hearing: a pair of clean earmuffs were provided, and boy, did I need them. The sound was loud due to the rather closed room with little ventilation (and therefore, dark).
Conclusion: Recommended. Good fun with a steep price.
This review is the subjective opinion of a TripAdvisor member and not of TripAdvisor LLC.