Flintlock fit tweaking on Lyman GPR: How to approach advise requested?

[JPK]

Put the barrel in and lock screwed in, then remove the barrel. Is the barrel dragging on the lock? Loose the lock and place the barrel in with a small bit of paper along the barrel where the bolster will touch the barrel then tighten the lock down. Will the paper come out or there be tearing and where did it stay?

[Daryl]

That depends on the fit, now, doesn't it. Why are you asking us, you're the one with the rifle.

[Oil Derek]

Put the barrel in and lock screwed in, then remove the barrel. Is the barrel dragging on the lock? Loose the lock and place the barrel in with a small bit of paper along the barrel where the bolster will touch the barrel then tighten the lock down. Will the paper come out or there be tearing and where did it stay?

I will try that jpk and post my findings, thanks.

[Oil Derek]

That depends on the fit, now, doesn't it. Why are you asking us, you're the one with the rifle.

Normally I esteem your posts, thanks for that valuable insight Daryl!

[Oil Derek]

Put the barrel in and lock screwed in, then remove the barrel. Is the barrel dragging on the lock? Loose the lock and place the barrel in with a small bit of paper along the barrel where the bolster will touch the barrel then tighten the lock down. Will the paper come out or there be tearing and where did it stay?

1). Barrel would come out with tightened lock; slight resistance and blackening was intact except for the flash shield/fence and one very small contact point at the front of the bolster.

2).  Paper tore along the flash shield and remained; some minor soot dragged off the entire length of the bolster.

[Daryl]

That depends on the fit, now, doesn't it. Why are you asking us, you're the one with the rifle.

Normally I esteem your posts, thanks for that valuable insight Daryl!

Sorry about that, didn't "see" who posted all the questions. Forgot it was your initial post. Oil D.

[Oil Derek]

Daryl, quite alright actually. Kinda *#)*^~ me off at first, but then it got me spurred on to really focus on solving the problem. And NOW I know what actually needs done.

I learned when assessing a problem, sometimes it is better to start out adding things rather than immediately removing things.  I cut a .030” credit card (x2) to the rough shape of the rear mortise and fit the lock and barrel together. Bingo, the non parallel gap went away 100% with full bolster to barrel contact.  Of course the rear plate was about .020” proud of the lock panel at the rear.  Now I either shim the rear mortise flat (.030”) or continue to take down the nose inlet. Nose is pretty deep as is, and don’t know if it close to breaking into the ramrod hole.  Decision time.


I did get creative out of curiosity.  I went to the anvil on my bench vise and pounded out and filed a copper slug (some would call it a penny ).  Cut and shaped it into a half moon and did a search about metal to wood glues. I might go that route and possibly pin it as well.

Derek, Out.

[Steeltrap]

Well....if you put in that piece of "copper"...you'll up the value of that rifle by a penny!!

[Oil Derek]

Well....if you put in that piece of "copper"...you'll up the value of that rifle by a penny!!

lol Steeltrap!  Maybe 1/10 of a cent with inflation and such.

Where do you draw the line concerning lock panel architecture if ⅛” has to come off the nose?

[Steeltrap]

Well....if you put in that piece of "copper"...you'll up the value of that rifle by a penny!!

lol Steeltrap!  Maybe 1/10 of a cent with inflation and such.

Where do you draw the line concerning lock panel architecture if ⅛” has to come off the nose?

I'm not quite sure what you are referring to when you say "nose". Do you mean in order to have the lock bolster fit properly against the barrel you have to remove (deepen) more wood (1/8") from the front of the lock mortise?

[Oil Derek]

Well....if you put in that piece of "copper"...you'll up the value of that rifle by a penny!!

lol Steeltrap!  Maybe 1/10 of a cent with inflation and such.

Where do you draw the line concerning lock panel architecture if ⅛” has to come off the nose?

I'm not quite sure what you are referring to when you say "nose". Do you mean in order to have the lock bolster fit properly against the barrel you have to remove (deepen) more wood (1/8") from the front of the lock mortise?

Yes exactly.  sitting in the mortise the front of the lock is 1/16” to 3/32” below flush with the panel edge while the rear of the lock sits flush.  If that makes sense.  Forgive my lack of proper terminology.

If I use a scraper to bring the panel closer to flush with the lock plate then the panels won’t be parallel and the molding that transitions to the fore stock will be minimal if not gone.

Thanks Steeltrap, you’re the only one hanging in there with me at this point.

[Steeltrap]

Ok, so the lock plate is flat. The lock bolster should run parallel with the lock plate. So, if you have the mortice inlet so that the lock plate bolster "mates" with the flat of the barrel, (both horizontally and vertically) that's "a good thing."

Now, once you have that accomplished, then you should be able to sand, scrape, chisel, shape, reshape the mortice that surrounds the lock. (Have the stock around the lock plate sanded\shaped to be parallel with the lock plate.)

If the bolster is parallel with the lock plate (and I can't think that it's not), and you have the bolster sitting flush against the barrel side, then you can shape the wooden stock around\to the lock plate.

I hope this helps

[JPK]

It would appear that the lock is bearing on the fence and holding the tail of the lock up. If you can file the fence down and maintain a straight surface to the front of the bolster that will allow the lock to set up against the barrel. Then add a filler to support the plate in the correct position. I’d use accur-glass so the plate is supported both front and back.

[Oil Derek]

It would appear that the lock is bearing on the fence and holding the tail of the lock up. If you can file the fence down and maintain a straight surface to the front of the bolster that will allow the lock to set up against the barrel. Then add a filler to support the plate in the correct position. I’d use accur-glass so the plate is supported both front and back.

Hi JPK.  I guess you kinda alluded to this in your first post. More details then and a much clearer head on my part, I might have gone this route. Jeff Talbert was right in that the mortise inlet wasn’t parallel with the barrel.  The fence and bolster are square.  I guess it could have been machined at an angle to take .020” off the fence to zero at the front of the bolster.  Then it would have required the lock being inlet an extra 20 thousands deeper into the mortise.  Guess it came down to where the correction angle was applied. 

My ship sailed into the fog and was committed to course as I made further adjustments to the mortise inletting and have mostly scraped the panel edge down to the lock plate.

Thanks for your additional help.

[Oil Derek]

Ok, so the lock plate is flat. The lock bolster should run parallel with the lock plate. So, if you have the mortice inlet so that the lock plate bolster "mates" with the flat of the barrel, (both horizontally and vertically) that's "a good thing."

Now, once you have that accomplished, then you should be able to sand, scrape, chisel, shape, reshape the mortice that surrounds the lock. (Have the stock around the lock plate sanded\shaped to be parallel with the lock plate.)

If the bolster is parallel with the lock plate (and I can't think that it's not), and you have the bolster sitting flush against the barrel side, then you can shape the wooden stock around\to the lock plate.

I hope this helps

Yep Steeltrap, that’s the approach I have taken.  Already have scraped the lock panel down almost flush with the lock.  So far about .040 has come off the front.  Will need to reshape, deepen and blend the the panel where it transitions into the fore stock.  Thanks for all your help.