Gunsmith on the North Shore

SteelShooter

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Have developed a hair trigger in my S&W 629 .44 mag, doesn't even require a trigger pull when the hammer is cocked, a soft tap on the side will drop the hammer.
 
how does such “develop”?
Not uncommon to fracture a sear.

This condition in S&W revolvers is called "push off." It is called push off because the test is to push on the cocked hammer with moderate pressure. If the cocked hammer can be pushed forward, then the revolver needs repair. When you have push off, it is possible that some parts are damaged or broken, but most cases, the parts are OK, and the problem is readily repairable. Note that when testing push off, you push on the hammer with just a few pounds of pressure. If you push as hard as you can, that is likely to damage things.

To understand how push off happens, you need to be familiar with the very unusual sear configuration in a S&W revolver. In these revolvers, the single action engagement point on the trigger is a sharp edge which engages with a small groove on the hammer. That groove on the hammer is typically .003 - .004 in depth. The small engagement depth is why S&W revolvers have the glass beak single action feel that they are famous for. I am not aware of any other firearms that use a similar arrangement.

For these triggers to function correctly, the engagement point on the trigger must be sharp, and at a precise angle. If it becomes dull or rounded, then push off will develop. In most cases a gunsmith with a proper jig can sharpen the trigger with a very few strokes of stone, and the issue is resolved. You could reasonably ask, if it needs a sharp edge, how long can it last? And the answer is that they usually last many, many thousands of rounds. Both the hammer and trigger surfaces are very hard, and this system turns out to work very well in real world use.

When a revolver has push off, the gunsmith will closely inspect both the hammer and the trigger. If the single action engagement groove on the hammer is damaged, the hammer needs to be replaced. And in some cases the trigger could also need to be replaced. But needing new parts is not too common. The gunsmith will also inspect the rebound spring, since a lightened spring, done as part of a trigger job, can contribute to this issue.
 
If you don't mind heading to Plaistow, NH, Anthony at Stateline Guns does good work.

Thank you. I’ll check them out. Northeast Arms does fine work and they’re overall pleasant enough, but they usually make me feel like I’m bothering them when I come in for gunsmith work, and that I’m imposing a burden on them.
 
This condition in S&W revolvers is called "push off." It is called push off because the test is to push on the cocked hammer with moderate pressure. If the cocked hammer can be pushed forward, then the revolver needs repair. When you have push off, it is possible that some parts are damaged or broken, but most cases, the parts are OK, and the problem is readily repairable. Note that when testing push off, you push on the hammer with just a few pounds of pressure. If you push as hard as you can, that is likely to damage things.

To understand how push off happens, you need to be familiar with the very unusual sear configuration in a S&W revolver. In these revolvers, the single action engagement point on the trigger is a sharp edge which engages with a small groove on the hammer. That groove on the hammer is typically .003 - .004 in depth. The small engagement depth is why S&W revolvers have the glass beak single action feel that they are famous for. I am not aware of any other firearms that use a similar arrangement.

For these triggers to function correctly, the engagement point on the trigger must be sharp, and at a precise angle. If it becomes dull or rounded, then push off will develop. In most cases a gunsmith with a proper jig can sharpen the trigger with a very few strokes of stone, and the issue is resolved. You could reasonably ask, if it needs a sharp edge, how long can it last? And the answer is that they usually last many, many thousands of rounds. Both the hammer and trigger surfaces are very hard, and this system turns out to work very well in real world use.

When a revolver has push off, the gunsmith will closely inspect both the hammer and the trigger. If the single action engagement groove on the hammer is damaged, the hammer needs to be replaced. And in some cases the trigger could also need to be replaced. But needing new parts is not too common. The gunsmith will also inspect the rebound spring, since a lightened spring, done as part of a trigger job, can contribute to this issue.

I did put about 3000 rounds through it in a few months before going to AK
 
I can assure you , you’re not bothering us one bit , sometimes we are just too busy trying to get other customers guns out the door to spend a lot of time chatting about a repair coming in , we try to be prompt with our repairs and cerakote jobs so it doesn’t leave a lot of time to really get into the how and why of incoming jobs

sorry you feel that way , we don’t mean to come off like that at all
 
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I can assure you , you’re not bothering us one bit , sometimes we are just too busy trying to get other customers guns out the door to spend a lot of time chatting about a repair coming in , we try to be prompt with our repairs and cerakote jobs so it doesn’t leave a lot of time to really get into the how and why of incoming jobs

sorry you feel that way , we don’t mean to come off like that at all

I wonder how it feels like with the bigger store. I remember many a Saturday in that broom closet wall to wall with people throwing guns at Steve and George to work on.
 
Northeast arms.

Did you try removing the plate and checking the springs? That should take a few seconds and springs for SW revolvers are cheap and very easy to replace.
 
Check your strain screw before you do anything. It may have backed out a little. The strain screw is the screw at the lower part of the grip.
 
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