Lyman GPR lock question

[Timber Wolf]

Pilgrim here, fresh off the boat so be gentle. I recently bought a new .54 Lyman GPR flinter to go with my .50 T/C Pennsylvania Hunter. I have not shot the GPR yet but assembled it and was checking the spark. I was not impressed with the weak spark from the white sawn “flint” it came with so decided to swap it out for a “real” English flint. I had previously purchased an assortment of English flints from TOTW. I picked the ones listed for the T/C as that is all I had then but this size, 5/8” X 3/4” is showing for the GPR as well.

The issue is the flint is hitting the pan on the outside, non-cut out edge. The cock on the GPR travels much farther down than the cock on my T/C. Using the same size flint on the T/C is not a problem, but the outer edge has beaten off on the flint in the GPR. The remainder actually hangs down in the pan. The new, real flint is approximately the same size as the one it came with. It is now throwing good spark and should work, but I don’t think this is right. I cut a notch in the leather so the flint is all the way back against the screw. The flint is hitting the frizzen half-way down now. If I used a shorter flint or backed it off any more it would hit even lower reducing “scrape time” or whatever the correct term is.

What say you?

 

[Phil Coffins]

Is the beveled edge up? If so turn it over and see how that works.

 

[Griz44Mag]

Not all locks of the same size will need the same size flint.
Work it out so the flint size you use fits the lock properly.
If it is hitting the pan, it's too big. If it hits the barrel it's too wide.
Pictures would be nice, lets the experts here (I am NOT one of them) help you get it working like a champ.

 

[Cowboy]

Sounds like you need 5/8” X 5/8” size flint. I’ve ran into that problem with these 5/8” flint’s before.

TOW sells that size. Tom Fuller English Flint’s. They come in 5/8” X 3/4” or 5/8”X 5/8”.

You definitely need the a shorter flint my friend.

https://www.trackofthewolf.com/List/Item.aspx/141/1/FLINT-ENG-5S
Respectfully, Cowboy

​

 

[Sidney Smith]

This is the second GPR related thread that mentions using 5\8 in flints. Did they change their lock size or something, because I use 3/4 x 7/8 flints in mine, and it works just fine and the flint doesnt doesn't bottom out anywhere?

 

[Cowboy]

This is the second GPR related thread that mentions using 5\8 in flints. Did they change their lock size or something, because I use 3/4 x 7/8 flints in mine, and it works just fine and the flint doesnt doesn't bottom out anywhere?

Unfortunately I don’t have an answer on wether they changed the GPR lock my friend.

Had a GPR flintlock that I used a 5/8”X7/8” flint and it didn’t bottom out on the pan either. Sold that GPR off some time back.

I did have a CVA Mnt. Rifle that the 5/8”X7/8” was bottoming out on the pan. I switched over to the 5/8”X5/8” flint and that cured the problem.

If the OP is bottoming out with the 5/8”X7/8” length flint and the flint’s all the way back against the Jaw screw? Then the only option is to go with a shorter length being a 5/8”X5/8”.

Again, I really don’t know if there was a change in the Lyman GPR lock my friend?

Respectfully, Cowboy

 

[springfield art]

Pilgrim here, fresh off the boat so be gentle. I recently bought a new .54 Lyman GPR flinter to go with my .50 T/C Pennsylvania Hunter. I have not shot the GPR yet but assembled it and was checking the spark. I was not impressed with the weak spark from the white sawn “flint” it came with so decided to swap it out for a “real” English flint. I had previously purchased an assortment of English flints from TOTW. I picked the ones listed for the T/C as that is all I had then but this size, 5/8” X 3/4” is showing for the GPR as well.

The issue is the flint is hitting the pan on the outside, non-cut out edge. The cock on the GPR travels much farther down than the cock on my T/C. Using the same size flint on the T/C is not a problem, but the outer edge has beaten off on the flint in the GPR. The remainder actually hangs down in the pan. The new, real flint is approximately the same size as the one it came with. It is now throwing good spark and should work, but I don’t think this is right. I cut a notch in the leather so the flint is all the way back against the screw. The flint is hitting the frizzen half-way down now. If I used a shorter flint or backed it off any more it would hit even lower reducing “scrape time” or whatever the correct term is.

What say you?

I recently read a post somewhere, the guy actually uses a power sander to thin or trim flints. One of the major lock-makers for flint guns offers a high-quality replacement lock for the GPR, I seem to recall. There's lots of "Art" mixed in with the "Science" of black powder shooting! Guess that's part of the fun! (Eye protection important!)

 

[bldtrailer]

You can notch the flints you have with a pr of plyers nibbling the back edge as needed to fit. also use thin leather (old wallets gloves) watch out for those flint shards the are sharp ! Diamond files work also

 

[ord sgt]

Is the beveled edge up? If so turn it over and see how that works.

On the face of the frizzen, how far up the face does the flint strike? Near the top? Or does it strike more toward the middle? If the bevel is on the top edge, it could be hitting the frizzen more to the middle. Turning the flint over will raise the point of impact.