[GunDr]

After firing the first shot, does pushing the forend forward release the action? or do you still need to push the release button?

Remove the trigger assembly and look at the two "wires" between the hammer and the action lock. Sounds as if the lower wire may be bent.

By the way...those two "wires" are called the "action slide lock springs"

When the hammer rotates forward, a knob on the left side of the hammer cams the lower spring down, in-turn rotating the action bar lock down from behind the action bar.

Doug

 

[johnpe]

GunDr. Thanks for the reply. In shooting singles, the slide works exactly as it should. Frankly, when I've tried to fire two shots, I just work with it until the gun load again. I know I didn't have to push the forearm forward to unlatch it. The recoil does that will all loads. The last time I tried to shoot two shots was a number of years ago. I finally just gave up trying and either used another gun, M12 or O/U. I don't remember if I had to push up on the release, but is surely a possibility.

Johnpe

 

[johnpe]

GunDr. I've looked at the two wires on the left side of the trigger. Both are straight with one on top and one under the hammer lug. I've also looked at the wire positions on two other trigger groups and they are all the same. However, maybe tomorrow but surely by this weekend, I'll take the gun to the club with one of the other trigger groups and give it a try. Both triggers in the gun work well in the dry fire situation.

Johnpe

 

[GunDr]

The first step is making sure the action bar lock is rotating when you actually fire the gun while a second round is in the mag tube.

If the gun opens fine each and everytime you only load one round, and the problem comes with a second round in the mag tube, there might be a problem with the shell latch getting jammed by that round. If the shell latch is stuck, the action will not work.

 

[wm rike]

I only know the guts of a M12 well enough to disassemble and clean the theng, and put it back together without any parts left over. That said, my two 12s (a 12 and a 20), if fired with one hand, will recoil away from the forearm so as to unlock the action, then catch the forearm and throw it rearward sufficiently to eject the shell - an auto ejector! You might try that to see if the basic dynamics of the gun are in place, and trouble-shoot from there.

 

[johnpe]

Thanks for the replies. I've removed all three trigger groups from their guns and tried them while holding the hammers, pulling the triggers and watching the slide lock latch. As the hammer moves forward the latch on all three sets rotate upward - as they do as in pushing it up manually to release the slide. I think the offending gun's trigger group is working as it should. Turning the gun upside down and watching the shell latch shows it is rotating as it should. All three guns look the same in this regard. None the less, I've swapped out the trigger group and will give it a try this afternoon.

Johnpe

 

[johnpe]

Yesterday I took the offending M12 with a different trigger group out for a round of sporting clays. For the first time since I bought it in 1970 the gun went BANG-BANG, some of the time. The outing was quite instructive. It uncovered potentially two problems I've never encountered before in a M12. The shell in the magazine was not exiting onto the carrier smoothly and in one instance hung up about half way out of the magazine onto the carrier. To me this means that the carrier is too rough/too thick and/or the magazine spring is bad and a new one is needed. This is one of the last pre-64 M12's to leave the factory (August 16, 1963. Between now and this weekend, I will polish the inside of the carrier, stretch the spring, and give it another try. If it works, I'll probably order some new springs from Nu-Line next week. Comments will be appreciated.

Johnpe