The only difference between the Beretta model 84FS BB gun and the firearm is the ammo. You'll also notice less noise, MUCH cheaper ammo and have a lot more fun. Other than that, you won't be able to tell the difference.
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 Beretta features a semi automatic action that will empty its 17 round magazine as fast as you can pull the trigger whilst its blowback feature kicks the slide back with each shot giving realistic recoil.