This is not a replica, although it does shoot. It measures 16.6 centimeters and can shoot up to 2 meters. Pulling back the slide will cock the gun (and the useless external hammer). After the gun is cocked, the bullet can be loaded by dropping it into the barrel. Pulling the trigger will release the hammer and fire the bullet.
Quoting veLOLcerapter .
This sounds like an awesome mechanism, I'd love to build it, but how...
Could you maybe take a picture with the wall of the slide off to see the inside?
I apologize, but I've already taken it apart. Maybe I can explain though. The actual hammer (that pushes the bullet) is an 8 stud long technic axel. There is a rubber band on it to pull it forward. When the slide is pulled back, the axel is pulled behind the trigger mechanism (the part that holds it back) When the trigger is pulled, the axel is released and pushes the bullet out of the gun.
I'm sorry that I have no pictures, but I hope that makes sense.