it depends on what capacity ammo box you have. I can't remember the numbers in the small box. I want to say about 40 rounds, and the large is around 60, but you can jam more in there if need be. I haven't touched one for a year and a half, so my speculations could be off now. It is a great weapon if you have the skill to control it off the TnE. However, it does not have good penetration power for solid buildings. It is primarily an anit-personnel weapon. It will penetrate vehicles with ease though. I could go on and on about how much fun it is.