Because this CO2 BB gun is such a close copy of the firearm- you’ll want to use it to maintain proficiency without the high ammo costs and range fees. You’ll get a lot of shooting done in your home with this handgun…and at just pennies a shot. The only difference between the Beretta model 84FS BB gun and the firearm is the ammo. Other than that- you won’t be able to tell the difference. You’ll also notice less noise, MUCH cheaper ammo and have a lot more fun. Beretta M84FS Pistol Features Uses a 12-gram CO2 cartridge Semiauto Blowback 17rd removable BB magazine Manual safety Fixed front and rear sights Single-action