Chronograph Results - Lyman .50 Great Plains Flintlock

[Semisane]

Here's one for the anal among us. Forty-five shots in heat and humidity. Am I a trooper, or what? :wink:

 

[cynthialee]

Interesting how the second and third shot often are slower ...

 

[Renegade Dan]

That's good Stuff! :thumbsup: Thanks for sharing Semisane. All that shooting in hot humid weather, now I know why your called semisane. :wink:

 

[Carl Fowler III]

Appreciate you taking the time to post your results, my cousin will use your results to settle upon his hunt'n load! :v

 

[Billnpatti]

I commend you for your dedication in gathering this data. I was looking at it and noticed a strange thing that I didn't expect and that was a lack of a pattern when looking at the difference between the MV with regard to the increase in powder charge. Here is what I found starting with your starting charge of 50 grain and calculating the change in MV as your charge increased. It was not linear at all or even close. Here are the deltas starting at 50 grains: 43, 59, 84, 21,70,27, 19, 33, 65, 11, 28, 28, 80,31. I would have expected something resembling linearity until your charge exceeded the maximum effective load and then I would expect to see the delta become non-linear and drop off. This did not happen with your data. It would appear that there was nothing wrong with your paradigm nor technique so this is an interesting (puzzling) conundrum. Do you have any thoughts on it?

 

[Semisane]

Do have one thought on it Billenpatti, though it may be way off base.

I was not using a stop collar on the loading rod to assure equal compression of the loads. So even though I was trying to have the ball just touch the powder charge I could well have had different compression between shot strings (after letting the barrel cool for five minutes) or even within the same string.

CORRECTION: The figure shown in the table for Shot #2 of the 80 grain load should be 1563, not 1463.

 

[Dave K]

The pics or documents are no longer available?

 

[Semisane]

Dang it! I corrected the bad figure in Photobucket and forgot it would wipe out the original link.

Here it is again, corrected.

 

[Mr.D123]

Did you wipe between shots?

 

[Flint62Smoothie]

His chart data says wiped w/ alcohol patch, both sides, between shots ...

 

[Mr.D123]

Perhaps if I read that's I would've know. I just looked at the results. :redface:

 

[Dean2]

Nice work and good job of laying it out so it is real easy to understand. That is a lot of shooting in hot muggy weather. Thanks for sharing.

 

[Billnpatti]

I am still puzzling over your chronograph results. I went back and re-examined the data and then I saw one thing that caught my attention. It is the location of the chronograph in relation to your muzzle. You have it at 15 feet. If you are shooting a centerfire rifle, that is a good distance but it may not give good accurate results with a muzzleloader. It may be close enough that the patch could possibly be passing through the screens right behind the ball and causing erroneous results. I can't say for sure if that is what happened in your case but it could answer the question of the scattering of the velocities with respect to the powder charge. When I chronograph a muzzleloading rifle, I usually have my chronograph set out at 15 yards just to make sure that the patch has dropped away from the ball before the ball passes through the screens. I usually find my patches laying at about 15 yards. Anyway, it is just a thought for your consideration. :thumbsup:

 

[Semisane]

I think Bill has hit on something. Many, if not most of the patches fell beyond the chrono. Some off to the side. But some on a line between the chrono and the target.

Next time out I'll repeat a few of the loads with the chrono farther out and see what happens.

Thanks Bill.

 

[petew]

It would be interesting to see the results using 3F powder , and where the 2F and 3F meet performance wise.

As for velocities being scattered a bit, I expect using volume measure not a scale like the center fire guys use will have a great deal to do with that. Take the average and live with it , works for me.
Pete