Restoring a big French lock to flintlock

[rich pierce]

I bought a relic 1700s French lock I intend to restore to flintlock to use in a composite gun project. I found a frizzen, cock, and sear spring that should work. The challenge will be to find or fabricate a  pan/bolster assembly. It’s well beyond my blacksmithing skills. Are there sources for castings? Most if not all TRS locks are cast with integral pans. Fabricate or but a lick plate and harvest the pan?

[Robert Wolfe]

Can you buy a plate (with pan) from Rifle Shoppe that you like and cut off the pan and install it on your plate? Lots of cutting and filing but less than going from scratch.

[rich pierce]

Can you buy a plate (with pan) from Rifle Shoppe that you like and cut off the pan and install it on your plate? Lots of cutting and filing but less than going from scratch.

Robert, I’m leaning that way. I’m hoping for input on which lock plate this is, assuming it’s military. To my untrained eye there’s not much difference in plate styles between the 1716 Marine fusil orginaire to the 1763 infantry musket. Will see if Flinter Nick can steer me the right way on which it likely is.  Also hoping JTR and other restorers chime in.

[2 shots]

  hI, later 63/66 french musket locks have separate steel  pan/ bolsters,  maybe one of those could be made to work. try T.R.S.

[rich pierce]

  hI, later 63/66 french musket locks have separate steel  pan/ bolsters,  maybe one of those could be made to work. try T.R.S.

Thanks, just noted that TRS has separate pans for the 1763 and the 1763-66 French muskets.

[rich pierce]

TRS had a pan in stock that may work. Yay!

[2 shots]

  good luck with it. keep us posted.

[JTR]

Rich, I'd go about it just as you are. I'd find a suitably sized and shaped replaceable pan, then file, and weld it if necessary, until it fits.
John

[Joe Stein]

This will be interesting to follow. Thank you for posting, Rich.

[Clark Badgett]

What size is the lock?

[rich pierce]

What size is the lock?

6 and 1/8” long.

I got a pan from TRS that is perfect to fit. It’s coming along.

[Joe Stein]

Looks like you are well on your way to a complete lock.

[Bob Gerard]

Very cool project. I’m curious if the photo shows the actual half cock position. With a flint in the jaws, it looks like the frizzen will not be closed on the pan.

[silky]

Rich,

How do you approach the screw hole issue, assuming they’re not tapped to modern thread specs? Drill them out to a larger diameter and re-tap? Weld them over? Or maybe the originals are re-usable.

Thanks for sharing this — looks like a fun project!

- Tom

[FlinterNick]

hi Tom / Silkly

It’s almost impossible to match the original threads of the screws, I’m sure you know this and it’s a Great topic of discussion.

France used a pre-metric system that was more or less chaotic, screws would differ from factory to factory and village to village and smith to smith.

However, the one thing they did do according to Jess Melot was they would often use the existing plates as taps with iron blacks, this apparently is very possible due to the wrought iron being so soft in an annealed state. So replacing screws was reverse engineered in a way. It can be done today, however one wrought iron dowel or pin is costly.

For customers only i will at their request cut a new screw out of copper (craft store stuff) and send it to a die making company to have a die and tap made, customer has to buy it though, around $300 bucks.

[rich pierce]

Thanks for the interest and comments. The frizzen is rough fitted at the moment.  I’ll have to fiddle with it to get a decent seal, then I can drill it. The lock plate is very hard. The case hardening will cause a file to skate. So if I cannot make screws that fit existing threads, I’ll have to spot anneal, drill and tap to a larger size. I have period screw plates ( multi-hole dies that swage rather than cut threads) and I can tell the existing screws are close to some of the threaded holes in the English screw plate. The toughest will be the frizzen pivot screw where the threaded portion is long.

[bluenoser]

Thanks for the tip about making a copper try screw.  It will come in handy and I would never have thought of it.  Copper wire should work well and diameters ranging up to about 1/4" are on hand.
Always a good day when one discovers a new solution to a problem.

[FlinterNick]

Thanks for the tip about making a copper try screw.  It will come in handy and I would never have thought of it.  Copper wire should work well and diameters ranging up to about 1/4" are on hand.
Always a good day when one discovers a new solution to a problem.

You can use almost anything soft, I’ve tried wet wood, glue sticks and even twizlers candy (stale Halloween candy) anything that can take the thread shape will enable you to measure the pitch.

The closest thread i matched a 1763 charleville to was around 10 x 25 nearest to a m6 x 1,.

[bluenoser]

I have used wood in the past and was not satisfied with the quality of the imprint.  Twizzlers don't stay around long enough to get stale

[FlinterNick]

  hI, later 63/66 french musket locks have separate steel  pan/ bolsters,  maybe one of those could be made to work. try T.R.S.

Thanks, just noted that TRS has separate pans for the 1763 and the 1763-66 French muskets.

Some of their French locks don’t use a detached pan and were casted as one I’m guessing because of the molding process it worked better.

Many of the original French locks i’ve worked on the pans were so tight i don’t think they were ever removed, almost welded on or hammer forged. I’ve often suggested to the owners to leave them be.

I’ve also had requests to detach casted pans like the originals, you have to destroy a plate in order to do it. Or surgically cut the pan at the bolster and belly if you have an edm saw/cutter, it works great.

The locks with the best detached pans were Dutch. All of my original Dutch locks i can remove the pans easily.

[Hudnut]

Cast or forged one piece?

[JTR]

Rich, coming along nicely!
John