Lock Too Tuned?

[Halftail]

I sent away a Flintlock Lock to get "tuned".The gunsmith told me that it wasen't "too Bad" as is.I insisted he make it just that much better.He did a great job and it has an Awsome light trigger pull now.Sometimes it's too Awsome and goes off only seconds after cocking,even before getting ready to shoot.Not a good thing,I know.Luckily I got smarts enough not to go around pointing at things I don't wanna kill.This hasen't happened alot.Only a few times in the last year and it seems if I hold a light enough pressure on the back side of the trigger that it engages Better.What part has been taken down too much?The Lock is an L&R.Here is a Picture...

If I posted this in the wrong forum please move it.

 

You really need to pull the lock and take a picture of the sear/tumbler relationship. It sounds like maybe the sear isn't matching up just right to the full-cock notch in the tumbler, and a little bit of work with a stone might make it safer. That's just speculation though, we really need to see a pic of the other side of the lock to see what's happening.

 

[Halftail]

Here is a picture of a lock fully engaged

Here is one of it relaxed..

Do these help?

 

[LRB]

What static said, but you also should check to see if the trigger itself is pressureing the sear. You say that if you pressure the trigger forward you get better engagement. If your smith lightened the sear spring, which he should, it may no longer overcome pressure from the trigger which has likely been there all along. You may need to remove some metal from the trigger to allow full sear engagement.

 

[Birddog6]

The first thing you need to do is determine if it is the Lock or the Rifle.

Take the lock out, put a flint or wedge of wood in the jaw, cock it to full clock, close the frizzen & dry fire the lock & see if it is that touchy. Look at the sear & see if it is going fulling engaging into the tumber when it goes to full cock. Possibly the sear arm is too weak, or it is getting bound by wood when ya put it in the rifle. Maybe the sear arm is hitting wood in the stock ? It may be the triggerbar is too tight on the sear arm & putting pressure on it ? Or if the lock is not inletted into the lock inlet properly & you are torquing it, etc., etc., etc.

Several things you need to check out BEFORE ya start tuning on what ya just had tuned.....

 

Good point, LRB. The top pic is a tad blurry, so it's difficult to see the sear to tumbler relationship... seems you could sorta tell if it was a problem with the sear/tumbler by seeing how much pressure it takes to fire the lock out of the gun? Is there any play in the trigger when it's cocked?

 

[Halftail]

What static said, but you also should check to see if the trigger itself is pressureing the sear. You say that if you pressure the trigger forward you get better engagement. If your smith lightened the sear spring, which he should, it may no longer overcome pressure from the trigger which has likely been there all along. You may need to remove some metal from the trigger to allow full sear engagement.

Funny you should say that.When it first happened I pulled my trigger out and looked at my spring(Lyman trigger and I'm not a gunsmith so I hope you understand what I'm saying)I figured it to be too stiff.So I tried to take some of the springyness(is that a word?)out of it by bending it.That never worked so I filed so off of my trigger part that Engages the lock.That worked for awhile then the problem started again.Then I filed some more off.That worked fine for awhile now it's started sagin.Would a thing like over oiling the insides of my lock cause it to prematurly go off?

 

[Halftail]

Take the lock out, put a flint or wedge of wood in the jaw, cock it to full clock, close the frizzen & dry fire the lock & see if it is that touchy.

Birddog,
I'll give that a try.

 

[MikeChapin]

...This hasen't happened alot.Only a few times in the last year and it seems if I hold a light enough pressure on the back side of the trigger that it engages Better.What part has been taken down too much?The Lock is an L&R....

It sounds as if your trigger is a little too tall and is touching the sear enough to not let it engage the tumbler properly. Just a guess but I'll bet you have no slack at all in the trigger.

You should do what static said, pull the lock and make sure you are getting good engagement of the tumbler and sear. If you are, pull the trigger and take a moto-tool or some other small grinder and take a little off the top of the trigger so that you have a little slack.

 

[fishdog]

It sounds like the lock is fine.Try a small washer under the trigger for a test. If the lock does not fire thats the problem. Test and try different size shims until its good. Then file the trigger down the same amount as the shims.

 

[charcloth]

Hey Halftail,

I had a similiar problem with two of my "highly tuned" L&R's. One of them had a worn fly. New fly fixed the problem. The other wouldn't fully engage the full cock notch unless I pulled it all the way back and eased it forward into the notch. Since these fixes were discovered they have performed wonderfully.

Charcloth.

 

[Halftail]

The first thing you need to do is determine if it is the Lock or the Rifle.

Take the lock out, put a flint or wedge of wood in the jaw, cock it to full clock, close the frizzen & dry fire the lock & see if it is that touchy. Look at the sear & see if it is going fulling engaging into the tumber when it goes to full cock. Possibly the sear arm is too weak, or it is getting bound by wood when ya put it in the rifle. Maybe the sear arm is hitting wood in the stock ? It may be the triggerbar is too tight on the sear arm & putting pressure on it ? Or if the lock is not inletted into the lock inlet properly & you are torquing it, etc., etc., etc.

Several things you need to check out BEFORE ya start tuning on what ya just had tuned.....

This reply is to all that are interested in helping,
I figured I'd take someones advice and check the lock first.This didn't happen everytime but it happened some....I pulled the lock and tried to full cock it and when it hit the notch where the Sear goes into the tumbler at Full Cock(Just behind the fly)it did not engage every time.Holding the lock in an upright position and forcing the Sear down while cocking seemed to make it engage fully everytime.

 

[Birddog6]

Sounds like the sear spring is weak if it is not pushing it fulling into the notch. Or possibly the sear is binding..... Loosen the screw a tad & see if that helps. If it does the sear is binding against the lockplate.

 

[mikelange]

If the nose (the part that engages the tumbler notches) or the arm of the sear is dragging on the lockplate or, less likely, the inside face of the bridle, you should see faint wear marks where this is happening. If this is the case, you need to very slightly relieve the portion of the sear that's dragging. The suggestion that the sear spring is weak sounds good, too. Try bending the spring to put more pressure on the sear. If this turns out to be the problem, I'd just get a new sear spring from L&R and live with the marginally heavier trigger pull. Better that than always be wondering when the gun's going to go off on its own again.

 

[flaming canvas]

Since no one else has brought it up, is the fly moving freely when you bring it to full cock?

If its catching on the sear it could cause the problem you are having.

 

[Halftail]

The fly appears to be moving freely.The sear spring,I would say is weak.I guess a call to L&R for a chat and maybe some parts is in order today.

 

[LRB]

A lock with correct angles in the sear nose, and tumbler notch will stay cocked without a sear spring, when hand set. If it won't, the angles need adjustment to be safe. If this is the case with the lock in question, while a stronger spring may solve the problem for now, with time and wear, it could reappear along with Murphy's law. I would suggest that you give it a test and see, before you rely on just a stronger spring.

 

[Halftail]

I would suggest that you give it a test and see, before you rely on just a stronger spring.

OK,
I understand.I must seem pretty Green to you guys but is removal of the sear spring just a simple as removing the screw?Is a vice needed to uninstall or install a new one?

 

[rich pierce]

Can't solve this on a message board- you need a gunsmith to look it over and fix it. Not the guy who tuned it, obviously.

 

[Russ T Frizzen]

You should be able to remove and replace the sear spring using only a screwdriver and your fingers.