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@Loja man looking at those patches I’d say the crown on your rifle could use some smoothing. If I zoom in on the thicker patches that survived while you can see little holes where the lands would be. Either way, at least you found a patch thickness that’ll hold up. Did your groups tighten up at all?
So…I was using a tree for a rest since our bench (AKA picnic table) was not in a usable location. I only shot 4 shots this way at 25y. Not a great pattern. But I was not taking my time either. In the failing light I was more looking for patches. Next time I head out I will work more on the load and accuracy.
Will try to work some on the crown. Dose it seam strange with this being a older kit that has seen some use for the crown not to have been smoothed already?
 

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I guess it would depend on whether anyone messed with it. If they didn’t know any better (like me at first) or never looked at patches they may not have noticed it. Who knows? A little piece of 320 grit and your thumb will smooth it right out real quick.
 
@Loja man, your rifle probably hasn't been shot enough to smooth out all the sharp edges. Probably less than 200 rounds. The tiny holes in the patches indicate sharp lands, but not so sharp as using the best patch to ball. The donut holed patches are the indication of a sharp crown. @Stykbow's suggestion of 320 wet or dry sandpaper and the thumb to smooth out the crown. Rotate the sandpaper and thumb a few times then rotate the barrel 1/4 turn and rub the crown the same as before. Repeat until you have fully rotated the barrel for an even crown smoothing. Then try the smaller ball with thicker patching. The patch material has been washed? It will be softer to hold the lube better and conform to the grooves preventing gas cutting.
 
@Loja man, your rifle probably hasn't been shot enough to smooth out all the sharp edges. Probably less than 200 rounds. The tiny holes in the patches indicate sharp lands, but not so sharp as using the best patch to ball. The donut holed patches are the indication of a sharp crown. @Stykbow's suggestion of 320 wet or dry sandpaper and the thumb to smooth out the crown. Rotate the sandpaper and thumb a few times then rotate the barrel 1/4 turn and rub the crown the same as before. Repeat until you have fully rotated the barrel for an even crown smoothing. Then try the smaller ball with thicker patching. The patch material has been washed? It will be softer to hold the lube better and conform to the grooves preventing gas cutting.
Grenadier,
Yes, I did wash the patch material. I was just using avocado cooking oil as lube because that’s what I had on hand. I will for sure work the crown over before next range trip! Will report back in a few days!
Aaron
 
There are a number of Lyman GPR users out there including me and as fall is approaching. I think we should talk a little about our guns . This is one of the few production guns that looks kind-of like the Hawkin profile that we all love. When I got back into Black Powder 5 years ago this was the only reasonably priced "Plains Rifle" that I could find. Mine cost about $500 back then and although not perfect is a good shooter and a robust design. The new Pedersoli GPR's look even better than the old Investarms ones did and are a bit more expensive but reasonable compared to any kind of simi production gun.

My hunting load is a .530 swaged ball ,110 grs. of Graff FFF, .015 TC pre lubed patches and CCI or Remington #11 caps. Although I haven't killed anything but paper with it , I love to carry it around in the woods.

I would really love to see what some of you guys have done with the kit built version. So post about your GPR , add pictures , tell us what you like , and lets get excited about Fall which is right around the corner.

Some years ago I bought a left-handed flintlock Lyman GP in 50 caliber. Have shot it a lot in competitions and for hunting, using round ball for shoots and hunting. Did have to open up the vent to 1/16th inch to get reliable ignition. During the COVID shut down I stripped the blued finish off all the steel parts and refinished with Laurel Moutain browning solution. Steamed the dents out of the wood, sanded very lightly and rubbed on a couple of coats of Formby's Tung Oil. Am surprised at how much this changed the character of the rifle.

After a good deal of testing the hunting load is 90 grns of GOEX 3Fg, a thin card wad, .490 ball, cut at the muzzle patch of Wally Mart ticking lubed with 50/50 +/- lamb tallow/bee's wax. The card wad is to keep the patch lube out of the powder charge. Colorado ML season is in mid-September, and it can get pretty warm where I hunt from ambush, warm enough to make the lube pretty runny. Also warm enough to get me to fall asleep. Good enough for a muley doe on 12 September.
 
Some years ago I bought a left-handed flintlock Lyman GP in 50 caliber. Have shot it a lot in competitions and for hunting, using round ball for shoots and hunting. Did have to open up the vent to 1/16th inch to get reliable ignition. During the COVID shut down I stripped the blued finish off all the steel parts and refinished with Laurel Moutain browning solution. Steamed the dents out of the wood, sanded very lightly and rubbed on a couple of coats of Formby's Tung Oil. Am surprised at how much this changed the character of the rifle.

After a good deal of testing the hunting load is 90 grns of GOEX 3Fg, a thin card wad, .490 ball, cut at the muzzle patch of Wally Mart ticking lubed with 50/50 +/- lamb tallow/bee's wax. The card wad is to keep the patch lube out of the powder charge. Colorado ML season is in mid-September, and it can get pretty warm where I hunt from ambush, warm enough to make the lube pretty runny. Also warm enough to get me to fall asleep. Good enough for a muley doe on 12 September.
OK…you can’t just leave us hanging like this…we must have pictures of the finished rifle! Sounds beautiful.
 
Nice! It is interesting to see the various front sight heights on your rifles. Is that by design, or just because the rear sights for each are slightly different?


There are slight differences in the height of the front sights depending on what rear sight I used. Three of them had been filed/sighted in. The third one down had not been sighted in/filed yet at the time I took that pic.
 
My son has a 50 caliber Investarms Lyman GPR with the fast twist barrel and he likes it. I currently have two Lyman GPRs-a Pedersoli 50 caliber flintlock and an Investarms 54 caliber percussion. Both started out as kits. I used the factory supplied parts for the 50 caliber flintlock and a maple fullstock, along with other assorted small parts, that I bought from TOW for the 54 caliber percussion. The fullstock build was quite a challenge for someone as clumsy as I am but I think it turned out pretty darn good. TOWs opinion of a rifle stock being pre-inletted and my thoughts on the subject were definitely quite different. Overall, I like the Pedersoli version of the GPR better than the Investarms. The Pedersoli has much more refined hardware (trigger guard, nose cap etc.) than the Investarms version. I am quite impressed with the overall quality of both and would not hesitate to recommend either one to anyone.
View attachment 164784View attachment 164785




Nice work on that full stock @LSB!
 
I guess demand for GPR's is at an record high. Sorry to all who have asked but I sold my 10 year old percussion NOS GPR recently. It was beautiful and went for an astounding amount (near 8 bills). I always liked my "improved", flint, GPR better and retain the 2 barrel custom "frankenhawk" below for percussion use,
 

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54 cal
120gr of FF 777
.005 lubed patch
Lubed wad between powder and ball
Some WW added to the roundball

My rifle must be weird, because it goes against most BP advice.
It doesn't mind the hardened ball.
The more powder, the tighter it groups.
The .005 patches shoot better than the tighter ones.spent 3 days years ago trying and recording different combinations. This is what she prefers.

She might be weird. But wouldn't trade her.
They say every gun has it's sweet spot! Your results are proof!
 
well one of me has been arguing with the other of me about shooting the new to me Lyman gpr flinter with the never fired .54 barrel on it.
the shooter me won over the seller me. i have so little invested in this gun i thought to sell it with the .50 barrel and the .54 barrel and finance some parts for a build. silly me had to go and shoot it.
60 yards
.535 prb
.010 patch with bear oil
54g ff homemade
off a bench cause i was shaking like a leaf.
sticker bull was a 1.5 inch pastie.
this one is staying in my collection.
the clutter on the target was patterning my 11gauge with bismuth. not satisfied with results.20221009_161300.jpg
 
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well one of me has been arguing with the other of me about shooting the new to me Lyman gpr flinter with the never fired .54 barrel on it.
the shooter me won over the seller me. i have so little invested in this gun i thought to sell it with the .50 barrel and the .54 barrel and finance some parts for a build. silly me had to go and shoot it.
60 yards
.535 prb
.010 patch with bear oil
54g ff homemade
off a bench cause i was shaking like a leaf.
sticker bull was a 1.5 inch pastie.
this one is staying in my collection.
the clutter on the target was patterning my 11gauge with bismuth. not satisfied with results.View attachment 167499
I think you made the right decision to shoot it. It appears to be a good one for your collection.
 
So I went back out yesterday afternoon to shoot my GPR. Before I went out l polished the cone starting with 320 and worked up to 600 grit. Thought I would start with the .020 patches. First three shots or so it was still shredding them and it was not shooting a consistent pattern. Tried a couple of the .022 canvas patches. These came out whole with no cut marks. But they were a bear to get down the barrel. Switched back to .020 patches. With the now dirty barrel it stopped cutting the patches. Was able to shoot about 8 shots in a 1.5” group with a few flyers in between. Swabed the boar with a few wet patches and tried again. The .020 patches were shredded again. But with the clean bore the .022 patches went down pretty easy. Was using 60-70 grains 3F Goex because I was out of my Tripple7. Definitely noticed a lot more fouling with the black powder versus the Tripple7. So after I got home I partially cleaned the barrel out. Then I went to town on it for a little while with some 4O steel wool. Then a little more brasso polish in a patch wrapped around the jag. Really hoping to get it to like the .020 patches! Forgot to take a picture of the target. Here are the patches. First picture is what I could find of the .020 patches. You can see the various conditions they were in depending on whether the barrel was dirty or not.
 

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