Some .58 Ball Velocity Data

[Semisane]

This one is kind of interesting guys.

On Saturday I shot a bunch of 5-shot groups to gather velocity data for my .58 GM/TC Hawken. For consistency, I used weighed loads that were the equivalent of 105 grains volume in my TC U-View powder measure. I shot GOEX FFg, GOEX FFFg, Jim Shockey Gold FFG, Triple Seven FFG, Pyrodex Select RS, and Pyrodex P.

Here's the data chart.



And here are the targets.













The Pyrodex P absolutely DESTROYED the patches. I found one wrapped around one of the wire "v" shooting guides on the chrono. All that was left to it was a wad of threads. That accounts for the total loss of accuracy and wide variance in velocities. However, I'm pretty sure that on the third shot on that target I failed to seat the ball after short starting it. (Got distracted swatting flies and wiping sweat.) Fortunately, it did the barrel no harm.

I was quite surprised to see how close the velocities were between GOEX and T7 in this barrel/caliber/load volume.

[nchawkeye]

It's funny how Goex does well in most of these tests...Did 777 also blow out patches???

[cayugad]

.066 is the BC of a .570 ball in case you want to run some numbers on those loads. That is some outstanding shooting. And if I had flies like that, I would put a dab of honey on a target and shoot the flies when they landed in the honey. They look about the size of that bulls eye....

Nice shooting.

[Semisane]

Originally Posted by nchawkeye

It's funny how Goex does well in most of these tests...Did 777 also blow out patches???

I really can't say whether T7 blew out the patches nchawkeye. I got a reasonably good group with it and didn't go looking for patches. But I don't think I could have gotten that kind of a group if the patches were blown.

Blown patches usually produce a very erratic group with no discernible pattern. Normally, a perfectly horizontal group like that would indicate wind drift. But there was no wind to speak of. It has to have been aiming error on my part. I'm perfectly capable of aiming error.

[Gm54-120]

Nice shooting. Im not much of a PRB shooter but if i ever get one it will be a 58cal or larger.

That JSG fps is pretty sad compared to the others.

[Semisane]

That JSG fps is pretty sad compared to the others.

I've gotten low readings with JSG every time I've chronoed it GM54-120. It's made no difference whether I was shooting conicals, sabots, or balls, heavy bullets or light, or whether I seated it hard or just touching the powder. However, it was the cleanest powder of them all by a significant amount. Except for the cost, I would use it for target shooting. But in my opinion it's way overpriced for what it is.

[rafsob]

Hey Semi, you have peeked my interest. I shoot a T/C Big Boar .58 cal. tht shoots PRB extremely well. I have yet to find a conical that will shoot well in it. But this little test of yours has shown me that I mus try it also.

I love shooting the PRB, but I really want a good conical. However, this is very interesting and great info. I will try to run this test this week and get back to you.

Thanks.

[lemoyne]

Rafsob
Have you tried Pyrodex P for conicals in your 58? That's what gave me the best results. I think that it upsets the lead better,other wise it is hard to get them to shoot accurate. With a paper cross patch and P the 400gr shoot decent. Lee

[deer655]

Thats amazing on a 450 fps loss on the JSG. Thats some good shooting; I wonder where the horizontal string using the t7 came from, although even that is good shooting. I wish I could still shoot iron sights but the ol eyes get a fuzzy picture now when I do. Good report.

[lemoyne]

The difference in velocity does not surprise some of us. It is roughly the same results as several of us have gotten I did my testing with APP and had a few feet per second more difference and the velocity with that powder is very erratic thats why the long range accuracy is poor.