So today was finally the day that I got out to shoot my two flintlocks on paper after struggling to figure out a good charge and how to aim them for a good two years of hauling them out to the club's black powder trail shoots.
I'd always gotten good enough results that I felt encouraged but often I'd miss the easy ones and be left wondering what happened.
I set up the targets at 25 yards since this was about finding the accurate charge and not about me. I also shot off a padded block supporting the fore stock roughly where I tend to hold it myself.
One is a Lyman GPR flintlock in .50Cal. The other an older custom made flintlock done by a local builder (Al Brown) that passed away a few years back. That one is in .45Cal and extra long with a nice light swamped barrel. Both use rifled barrels. The GPR using their usual 1:48 twist and the Al Brown rifle using a 1:60 twist or there abouts. I've heard from local folks that knew him that he used some of each as well as some others depending on the caliber.
The plan was to start at 30 grains and work up in 5 grain steps to find the sweet spot. The Al Brown rifle went first. At 30 I had three shots that were about 1 inch center to center. And as the charges went up in the 5 grain steps the groups opened up at a ratio directly proportional to the charge. I stopped at 50 grains because the group of three shots was the size of a large melon. I went back and tried two at 30 to be sure it wasn't a fluke and the two were neatly near the bull and and the lead rings on the paper were just about touching.
The Lyman GPR was pretty much a repeat performance. Neat tidy group of approximately 1 inch from 30 grains and opening up steadily until I stopped at 45 grains since I could see where the trend was going.
For those that have run such tests of their own did you find that as the charge went higher that the group size shrunk back down? If I pushed on to 55 to 70 grains would I see a return of the tighter grouping?
Not that I'm unhappy about using the lighter charge. I only shoot for fun so this will be a little more frugal on my powder supply. But I'm confused as the cap lock underhammer .50Cal rifle I bought turned out to have a sweet spot at just over 60 grains. Which is why I'm wondering if the flint locks would sharpen up again if I went higher.
I should have tried it while I was there. But it was getting late and I was getting cold.
I'd always gotten good enough results that I felt encouraged but often I'd miss the easy ones and be left wondering what happened.
I set up the targets at 25 yards since this was about finding the accurate charge and not about me. I also shot off a padded block supporting the fore stock roughly where I tend to hold it myself.
One is a Lyman GPR flintlock in .50Cal. The other an older custom made flintlock done by a local builder (Al Brown) that passed away a few years back. That one is in .45Cal and extra long with a nice light swamped barrel. Both use rifled barrels. The GPR using their usual 1:48 twist and the Al Brown rifle using a 1:60 twist or there abouts. I've heard from local folks that knew him that he used some of each as well as some others depending on the caliber.
The plan was to start at 30 grains and work up in 5 grain steps to find the sweet spot. The Al Brown rifle went first. At 30 I had three shots that were about 1 inch center to center. And as the charges went up in the 5 grain steps the groups opened up at a ratio directly proportional to the charge. I stopped at 50 grains because the group of three shots was the size of a large melon. I went back and tried two at 30 to be sure it wasn't a fluke and the two were neatly near the bull and and the lead rings on the paper were just about touching.
The Lyman GPR was pretty much a repeat performance. Neat tidy group of approximately 1 inch from 30 grains and opening up steadily until I stopped at 45 grains since I could see where the trend was going.
For those that have run such tests of their own did you find that as the charge went higher that the group size shrunk back down? If I pushed on to 55 to 70 grains would I see a return of the tighter grouping?
Not that I'm unhappy about using the lighter charge. I only shoot for fun so this will be a little more frugal on my powder supply. But I'm confused as the cap lock underhammer .50Cal rifle I bought turned out to have a sweet spot at just over 60 grains. Which is why I'm wondering if the flint locks would sharpen up again if I went higher.
I should have tried it while I was there. But it was getting late and I was getting cold.
