How long do your flints last? Or Tuning the Lock for Long Flint Life.

[BCRider]

I spent the last two days shooting in my club's Winter Rendezvous with my Lyman GPR flint lock. I found that I needed to knap the edge of the flint just about ever 6 to 7 shots. And by the end of the 25 shot trail the flint was basically dead meat on a stick.

Is this normal? I know the flints wear but I keep hearing that they should be good for closer to 40'ish shots before being replaced. I also understand that I need to knap the edge fresh a couple or three times during that lifespan.

these are English flints from TOTW. The flints are set so they begin riding on the frizzen at around 2/3's up the face and are showing signs on the frizzen wear of being more or less in steady contact the whole way down the face of the frizzen.

Is this normal? If not then is there some things I can do to stretch out the number of shots I can get before needing to re-knap? Any tuning of the mainspring to change the force of the hammer's fall? How does one test to see that the hammer is falling with the right force anyway?

 

[Patocazador]

I have about the same longevity with the black English flints and the Missouri chert ones, about 25-30 shots. The French amber flints last me a lot longer, about 80 to 100 shots.

 

[Armored farmer]

I have also found a big difference in flints.
I bought a bunch of french amber. One of those will last me an entire match day,maybe two.

 

[birdshot8's]

I was only getting about 7 clean shots from my English flint until I turned it over and used it with the bevel up. It changed the angle of contact enough to allow a more glancing contact slightly lower on the frizzen.
Before flipping the rock over I had tried French amber, English flints, Kansas chirt, and saw cut stones. All with disappointing results. I was ready to give up on flintlock, I am glad I stuck it out.

 

[BCRider]

Thanks birdshot, I'll give that a try.

 

[Loyalist Dave]

We could really use a photo of the face of your frizzen.

I usually get at least 30-40 shots from a flint...sometimes more.

What do you wrap your flint with? Leather or lead? It should be leather. There should be a cutout of the leather that allows the flint to touch your jaw screw.

Try this...take a small, Diamond Match brand, wooden match stick, used. Place it under the very back part of your flint, between the lower jaw and the flint, where it meets the jaw screw. Break off any part of the match stick that extends beyond the flint jaws. This will ever so slightly cant the edge of you flint downward. See if you still get good ignition, and try it with the flint both ways.

IF it's still eating flints, then you might want to polish, by hand, with emory paper, the cam on the bottom of the frizzen, and the frizzen spring where the cam touches...plus the sides of the frizzen where the frizzen screw passes through. Sometimes friction will cause the frizzen to be too stiff, and although the cock doesn't rebound, it still may be chipping off chunks of flint edge.

LD

 

[BCRider]

Thanks Dave. There's a few gold nuggets there that I'll have to work on.

I use the leather pad and they have the slot in the middle of the fold so the flint sits on the screw just as you describe.

OK, I just ran off and compared the GPR's frizzen to my .45's frizzen and I think you're onto at least one factor. The GPR frizzen is very much stiffer and stickier to move than the custom built and tuned lock on my .45. So that's a start for some tuning. And I know from shooting the .45 that the flints on it last a lot longer. Our BP trail is 25 shots long and with the .45 I only had to knap the flints about half to 2/3's along and it lasted the rest of the trail. And that's head and shoulders better then what I got this past weekend from the GPR.

After that I'll play with flipping and canting so it's striking the frizzen at more of a swiping angle than the direct on crash to the face that I see it has with the setup I was using this past weekend.

I'll mount a flint and get pictures to help you folks help me more on this setup aspect.

 

[Curator]

BCrider,

Lots of good advise here. Experience will show what angle your flints need to be to get best sparking and long life. As you have noticed, frizzen resistance is a big issue. GPRs do not have the best lock available. I have replaced several of these with after-market L&R replacement locks that use leaf springs and have roller firzzens. You can try polishing the frizzen friction points with #600 emery cloth to see if that helps.

 

[BCRider]

Everyone that brought up points in this thread please stand, take a bow and allow me to applaud to each and every one of you.

I spent some "quality time" with the GPR over the last couple of hours with the custom .45 sitting along side to compare.

The .45 has the roller as mentioned by someone above. I noticed that as the frizzen is lifted there isn't really any spring to the motion. For quite an angle it moves with pressure then stays put due to how the roller rides on the cam of the frizzen. Only at the end when the flint is about to skip over the lower edge of the face does it snap smartly out of the way.

Now for the GPR. First off it was stiff and rough as noted. But more importantly if lifted a hair it would spring back down instead of remaining in place. Also the flint was only about half way along the face when the cam riding directly on the spring jumped open. So no wonder I was seeing signs of uneven riding before.

So I did the following.

First was to take things apart and stone then polish the upper face of the frizzen spring. It was extremely rough and I suspect this helps a lot. The removal of enough steel to give it a smooth upper face likely also reduced the spring rate slightly. But the GPR was so much stronger than the custom tuned lock on the .45 that a slight bit of spring rate is well discarded. Following the smoothing of both the upper and lower arm outside faces of this spring edges were relieved and the bare metal blued.

The point on the frizzen cam was then polished.

Back together the frizzen moves easily but now the point where the frizzen snaps open occurs even sooner and with more snap. The loss of friction means it just won't sit in one spot for long.

So.... next up was take it apart again and this time I profiled the cam's finger to have more of a concentric shape with the inner hole. So now there's a duration of arc as it opens where it doesn't spring open. The flint can now ride the face pushing the frizzen easily with no spring resistance like there was before. The only thing holding the frizzen to the flint is the slight drag in the system. By eye and feel it's a very close match now for both resistance and drag to the roller cam frizzen on the custom .45. Before I started the drag and higher spring pressure on the GPR was easily felt.

I mounted a new flint but this one is a bit short. So it's already hitting the frizzen with a more swiping angle. The match stick trick will be kept for the next flint which is very likely to be a bit longer and want to strike a bit higher and more directly.

A dry fire test shows I'm also getting more sparks now too. It was never a strong sparker. And after working on it with help from you lot and studying the .45 I feel it's now as good as the custom rifle.

I'm as happy as a clam and I thank you all.

The life of the flint is still to be seen. But I'm not going to sit and dry fire it. I'll take it out and try it at the range instead since I also need to do some fine tuning on the sights. Long distance targets almost seem like child's play other than the truly diabolical ones. The targets that are giving me fits are close in. One is a long 2x4 loaded with golf balls on 5 inch dowels. The idea is to remove the ball. The other one is a vertical board with plastic forks sticking out. The goal being to remove some or all of the tines without breaking the handle The golf balls are about 10 to 12 yards away and the forks about 7 to 10 yards. I need to shoot close in on some paper to figure out the hold. That'll be a good time to see how many shots I get before needing to freshen the edge up.