bolt failing to lock back on full auto.

[hlake]

Hello,

Locking to purchase a S&W76. I test fired the gun and the bolt locks to the rear on semi auto but not full auto. Is this normal? Used 124 grain FMJ remington ammo for test fire. Only the same magazine for both full auto and semi auto.

Any help/suggestions are appreciated. Thanks

HLake

 

[BWE Firearms]

First use better ammo. Remington is not hot enough in most opened bolt subguns to drive the bolt far enough back to catch the sear.

 

[MachinegunKid1]

Remember, you can also test / verify sear function manually without the use of live ammo.

 

[Strangeranger]

Clarify "doesn't lock back" please. Does the gun run away, i.e. fire till empty? Or does it slam closed on a live round but not with enough energy to ignite the primer?

 

[hlake]

Thanks to all for the quick replies. I will try again with different ammo.

 

[Moose]

Hlake
Not sure exactly what you mean when the SW76 in question does not lock back, but I can explain mine. My 76 does not lock back when I finish firing a loaded magazine and now its empty, but does when the magazine has rounds in it. Like short bursts.
Does his help?
Moose