Then push in the breech release button and lift up the rear of the breech and
breech bolt as an assembly and withdraw to the rear, setting it aside.
Closing the finger lever elevates the locking bolt at the rear of the receiver into engagement with a deep slot on the underside of the
breech bolt.
Drop the hammer, remove the rear sight, re-cock the hammer and slide the
breech bolt from the receiver.
As the employee turned the handle on the
breech bolt, it was expelled into his leg by the gas.
As the employee turned the handle on the
breech bolt holding the round, it was forced out at high speed by the trapped gas.
When the
breech bolt is moved, the gun will jam with the bolt to the rear.
When a Benelli is fired, the mass of the
breech bolt remains stationary while a carefully calibrated spring pushes against the rotating bolt head, forcing it into tighter engagement with its matching cuts in the barrel extension.
"When the action-bar sleeve impacts against the front of the receiver, 5 ft-lbs of the 10 ft-lbs stored in the moving mass are put back into the equation and an instant later the
breech bolt, still moving rearward, impacts against the rear section of the receiver, putting back the other 5 ft-lbs, thus satisfying Newton's Law."
Depress the spring-loaded, small
breech bolt sleeve lock and rotate the
breech bolt sleeve counterclockwise (looking from the rear of the bolt).
Upon inspection, he determined that a GAU-8
Breech bolt firing pin had failed causing every seventh round not to fire.
If you are dealing with a semi-auto or lever gun where you cannot easily remove the
breech bolt to look through the bore, you can use a collimator to get the bore and crosshair intersection aligned as closely as you are able.