Lock Binding

[IanH]

Are you going to flip this or keep it?

 

[BigSkyRambler]

Are you going to flip this or keep it?

It's a Left-Handed SMR, so, flip. It also had a carved antler grease hole that the auction house managed to knock out while packing. Said they would cover cost of installing a patchbox, which my fingers can't handle. So I will make someone a great deal, if they want to take that on as well. Can't get anyone on here to throw me a ballpark figure on that one. Auction will pay shipping for work, too.

 

[SDSmlf]

Once in the lock mortice the set trigger does not engage and even half and full cock won't hold. So, what's the rub?

Once in the lock mortise WITHOUT the trigger installed does the lock hold at half and full cock?

 

[BigSkyRambler]

Once in the lock mortise WITHOUT the trigger installed does the lock hold at half and full cock?

Been too busy to take out trigers. Maybe tomorrow.

 

[Mgbruch]

I know ya'll are trying to help, but if only those who really understood how double-set triggers operated would post, this would be a lot less confusing.

The answer is the mainspring for the hammer trigger is following through too much.

For God's sakes quit filing on the sear bar and the trigger arms. You should be able to tell by the angle they cross through the sear bar hole that the trigger plate is NOT set too high. I do understand double set triggers; and have made my own for five rifles I've built.

Based

I know ya'll are trying to help, but if only those who really understood how double-set triggers operated would post, this would be a lot less confusing.

The answer is the mainspring for the hammer trigger is following through too much.

For God's sakes quit filing on the sear bar and the trigger arms. You should be able to tell by the angle they cross through the sear bar hole that the trigger plate is NOT set too high.

I do understand double set riggers; and have made my own for five rifles I've built. can't tell for certain, but based on the location of the sear arm to the bottom of the lock plate... And the location of the trigger bars in relation to the lock plate inlet, I would say the bars are too high. Yes, the main spring on the triggers is pushing the rear trigger bar up pretty high. That could be remedied with an adjustment screw to reduce the downward travel of the mainspring; or the rear trigger bar could be filed, or a combination of both.

If it were me... I would take the rear trigger off, put things back together, and see if the front trigger has enough clearance for the sear to engage the half cock and full cock notches. If not, then yes, I'd file the front trigger bar to get clearance. Once you know the front trigger is ok, install the rear. If there is no engagement with the notches, then the rear trigger bar is going up too high, and will need to be remedied by an adjustment screw, filing the bar, or both.

It's possible to adjust the set trigger mainspring (if you install a screw) so much that the force on the rear trigger is too light. You need a certain amount of inertia on that rear trigger for good fast action. A lot of double set triggers, mine included, don't have a mainspring adjustment screw. In that case, the trigger bar does need to be taken down... a little at a time.

 

[IanH]

It's a Left-Handed SMR, so, flip. It also had a carved antler grease hole that the auction house managed to knock out while packing. Said they would cover cost of installing a patchbox, which my fingers can't handle. So I will make someone a great deal, if they want to take that on as well. Can't get anyone on here to throw me a ballpark figure on that one. Auction will pay shipping for work, too.

That sucks about them losing the grease hole insert, I would like to have seen what that looked like. Maybe sell it cheap or ask someone if they could fix on your triggers up at the same time the other work is done.

 

[BigSkyRambler]

That sucks about them losing the grease hole insert, I would like to have seen what that looked like. Maybe sell it cheap or ask someone if they could fix on your triggers up at the same time the other work is done.

Before

After.

 

[oldwood]

Didn't see anyone suggesting to check how the trigger adjustment screw is set ?

 

[Flintandsteel]

Your trigger is putting pressure on the sear, not allowing it to drop into full and half cock notches.
There are several ways to fix it, but all have the Same results.
Don’t grind on the sear bar.
Lower trigger bar, or adjust the pressure of the trigger mainspring, or both.

 

[SDSmlf]

Your trigger is putting pressure on the sear, not allowing it to drop into full and half cock notches.
There are several ways to fix it, but all have the Same results.
Don’t grind on the sear bar.
Lower trigger bar, or adjust the pressure of the trigger mainspring, or both.

And does this apply if the lock installed on the gun doesn’t drop into half or full cock with the trigger removed from the gun? OP confirmed locked ‘worked without out triggers’ but has not confirmed lock worked in stock without triggers. Or maybe I missed something?

 

[IanH]

Thanks for the fotos, that was a cool addition that's been deleted. Looks like it was never fastened in and needed a countersunk brass screw in the bottom to hold it.

As for the triggers, the trigger mainspring and hammer trigger need to be set up so the mainspring hits a stop before the hammer trigger touches the sear bar. The hammer trigger should act on the sear bar through inertia only, no spring force carrying it through the full stroke. There should be slight clearance where the hammer trigger has some freeplay that allows the sear bar to move as the tumbler notches pass over it. The front trigger can ride the sear bar just fine as long as its feather spring is weak enough to allow the sear to firmly engage the tumbler. If the hammer trigger mainspring is putting force on the hammer trigger all the way through its travel, it will keep the sear bar disengaged all the time and it won't hold cock.

If the cock will engage fully in both of its notches with the hammer trigger set, then all that's needed is to shorten the nose of the hammer trigger spring, deepen the notch where the spring bears on the hammer trigger, or install a stop screw for the trigger mainspring right behind the hammer trigger in the bottom of the plate.

 

[cynthialee]

if it will trigger outside the gun with ease but binds in the gun then you probably have the lock plate too tight
probably need a small shim in there somewhere

 

[Snooterpup]

Might try that. Here is a photo of trigger bar. Does that look high? (In 3...2...1).View attachment 297742

Looks to me like you’ve got the set trigger adjustment screw way to far in. Back that screw out until it works.

 

[BigSkyRambler]

Looks to me like you’ve got the set trigger adjustment screw way to far in. Back that screw out until it works.

Derp! That was the problem. But I had to back it so far out, it seems almost, but not quite, loose. I had tried this earlier, but it was backing out so much that I figured it wasn't the problem . Is this normal. Not my behavior, which has been established as abnormal, but the set screw?

 

[Snooterpup]

Derp! That was the problem. But I had to back it so far out, it seems almost, but not quite, loose. I had tried this earlier, but it was backing out so much that I figured it wasn't the problem . Is this normal. Not my behavior, which has been established as abnormal, but the set screw?View attachment 298104

Since manufacturers make these set triggers for custom builds it’s not uncommon for them to be a bit too long. Remove the screw, carefully take off a thread or two. Just don’t take off too much! Am I entitled to a discount?
Just kidding.
When these problems occur I always remove the trigger group from the gun and actuate the installed lock with a small screwdriver or like item. It if works, no modifications are needed to the stock or the sear. Look to the trigger then.
Best wishes,
Snoot

 

[sturmkatze]

How do you reduce mainspring follow through? This is getting well outside my wheelhouse.

Listen to the other guys. Take the ?$&?/$& trigger out, see if it works then. Round the sear. Do not mess with the mainspring. If it’s too much, go to a BP gunsmith. These guys get paid to do this.

 

[Eric Krewson]

The trigger bars on my set and single triggers barely show in the sear holes. Yours definitely need some adjustment.

 

[Snooterpup]

In adjusting the set trigger, back it out, way out. Slow screw it in while trying it until the lock no longer functions. Back it out one full turn. This is your main adjustment. Make minor adjustments either way until you are satisfied.
Snoot

 

[BigSkyRambler]

In adjusting the set trigger, back it out, way out. Slow screw it in while trying it until the lock no longer functions. Back it out one full turn. This is your main adjustment. Make minor adjustments either way until you are satisfied.
Snoot

I'm just satisfied that I don't have to take everything apart and fiddle with it.

 

[IanH]

The only thing that screw adjusts is the amount of engagement the front trigger has on the rear trigger. If it is screwed in too far, the set trigger won't set. That screw has nothing to do with how much pressure or how much follow through the trigger mainspring puts on the hammer trigger.