Bend the sear bar up?

[WonkyEye]

This is my first build. Chambers Dale Johnson lock. The sear bar is so close to the edge of the lock plate 15/1000s, that I'm concerned. After polishing the edge of the plate it might even be even with the edge.

I'm thinking about bending it up 1/32" so it's not touching the wood. My hesitation is this lock works like a fine tuned clock, compared to my TC and my L&R it's a thing of mechanical beauty. I'd hate to cause a bigger problem.

I haven't inlet anything yet, I'm still working out layout and measurements. I'm taking my time and waiting for winter hibernation to really get going.

If I do bend, what's your tips for re-hardening and tempering the sear?

 

[wiscoaster]

Instead of bending, which I think is iffy anyway, and probably messes up your interaction with the trigger bar, it looks like you've got plenty enough material there to do some filing to give you a little more clearance.

 

[Phil Coffins]

I’d start by contacting Chambers and explaining the issue. They would be best qualified to answer any questions you have.

 

[wiscoaster]

Ya, that's an even better idea.

 

[Phil Coffins]

Move the hammer to half cock and the sear will probably be below the edge of the plate.

 

[ZUG]

If you do bend the sear bar you don't need to reharden it. The only reason that the whole sear is harden is because of the way they are manufactured. When made the whole sear is harden and tempered because it is easier to do it that way then to just harden only the nose of the sear. There is ample amount of steel in the sear bar that it will not deform from the action of the trigger and if you think you will wear the sear or trigger bar think again - it would take MANY years for that to happen. The only thing that you MAY notice is a rough trigger pull but not much if at all. That trigger bar is still hardened. There is not much movement between the sear and trigger bar so very little wear is between the two surfaces.

I've done a lot of "tweaking" on sear bars to give me more clearance (Clarence ). Do as Phil says to check if the sear drops below the plate when in full cock position if so call Jim Chambers.

 

[FlinterNick]

This is my first build. Chambers Dale Johnson lock. The sear bar is so close to the edge of the lock plate 15/1000s, that I'm concerned. After polishing the edge of the plate it might even be even with the edge.

I'm thinking about bending it up 1/32" so it's not touching the wood. My hesitation is this lock works like a fine tuned clock, compared to my TC and my L&R it's a thing of mechanical beauty. I'd hate to cause a bigger problem.

I haven't inlet anything yet, I'm still working out layout and measurements. I'm taking my time and waiting for winter hibernation to really get going.

If I do bend, what's your tips for re-hardening and tempering the sear?

Why would you bend it? Its where it is designed to be on the plate, the trigger contact is close, bending the sear will put it further away

 

[Larry (Omaha)]

Why would you bend it? Its where it is designed to be on the plate, the trigger contact is close, bending the sear will put it further away

For the sake of discussion and not argumentative. A sear below the plate causes issues when replacing and removing the lock.
What difference does it make if the sear is farther away from the trigger contact? A trigger bar has to fit the situation. (add or shorten hight of the bar) More thought please.
Larry

 

[FlinterNick]

Doesn’t look like it’s off the plate.

No issue

 

[FlinterNick]

For the sake of discussion and not argumentative. A sear below the plate causes issues when replacing and removing the lock.
What difference does it make if the sear is farther away from the trigger contact? A trigger bar has to fit the situation. (add or shorten hight of the bar) More thought please.
Larry

Regards to the sear being further … you’ll have a dangling trigger. When I build I try to fit the trigger so contact is close almost self setting

 

[Larry (Omaha)]

Regards to the sear being further … you’ll have a dangling trigger. When I build I try to fit the trigger so contact is close almost self setting

What is a dangling trigger? The bar needs to be as close to the sear as possible and maintain a free moving sear.
Larry

 

[garypl]

I had a Siler lock with the sear bar right at the edge - about the same as yours. I just cut a clearance notch inside the lock mortise and it went in and out of the lock mortise with no problems.

 

[EC121]

Silers(the Dale Johnson lock is a modified Siler) are made that way. You won't file anything off that hard metal, but since there is plenty of metal, a little judicious grinding will help you clearance.
For a bit of background. Dale took a Siler lock and sawed the plate almost in half. Then he bent the tail down about 1/8" to allow the tail to follow the wrist better, and welded the plate together. This along with undercutting the breechplug lug helps avoid the infamous humpbacked wrist. Jim then took the modified lock and used it to make the mold masters for casting.