58 caliber PRB loads

[Sparkitoff]

I can't find much info and data on PRB loads in 58 caliber. I see lots of info on Minnies. I have the components but haven't fired a single round yet. I planned to sight this in at 100-yards and then let my son tweak the sights and use it for deer hunting. Idea was to start with 80 grain Goex (and try 2 and 3F) since I use 80 grains in 3 other rifles. What is the approximate MV? The barrel is 28" or so ( I havent measured but its a carbine type). While its "just" a deer rifle I see velocities like 900 fps and that seems a little whimpy when a 54 PRB can do nearly twice that. I do have a chronograph to figure this out, just trying to get a head start with your personal experience. Thanks

 

[Grimord]

The twist rate of the barrel will determine the load with the best accuracy. In my .58's, my hunting load with PRB is 120 grains of 2f for about 1500 FPS and 3" at 100 yards though I would never shoot at a deer that far away as my eyes are not what the used to be. Both of my .58's have a 1:66 twist. I once had a T/C Big Boar .58 with the 1:48 twist. The most accurate hunting load with that gun was 100 Grains of 2f. If I tried to go higher, accuracy fell way off. I have tried using 3f at about a 10-15% reduction from the 2f loads, but accuracy was not as good, and the recoil seemed to be much sharper. 2F seems to be more of a push, whereas 3f was a real kick.

 

[rich pierce]

I shoot 90 grains of FFG behind a .570 round ball in my .58 with a 38” barrel. It is kind of lobbing it out there. I find it best to have it on at 75 yards.

 

[Rifleman1776]

The twist rate of the barrel will determine the load with the best accuracy.

Bingo. You need to determine the twist just to find a starting point. Caliber is only part of the equation.

 

[mooman76]

I shoot 80 out of mine for a hunting load. Less for just target plinking.

 

[Semisane]

A while back I did some chrono work with one of my .58's. Results below.

This is the best group I've ever gotten from the bench.

 

[TreeMan]

Years ago me and a buddy both had West Virginia Doe permits. I had a .570 roundball loaded with 60 grains of 3F Goex in a two band enfield. He and I were riding an ATV across a field when we stumbled across a few does grazing. I jumped off and laid the enfield across the seat of the ATV. I shot a doe broadsided at about 50-60 yards. It passed through her and hit another doe behind her that was facing me, dead in her chest. Both of them dropped dead there on the spot. That was many years ago and I can’t remember now whether I recovered the ball or not. Needless to say he had to use his permit to check in the second doe. Doesn’t take as much powder as people think.

 

[hanshi]

More powder doesn't necessarily mean a deader deer and that's for sure. RB penetration is much greater than most realize, with the velocity-flattening of the ball often the only thing keeping it from going through & through.

 

[Semisane]

The deer aren't deader with more powder, but the trajectory is flatter.

If your typical hunting situation is 75 yards or less, velocity is of little concern. If you situation presents 150 yard shots, higher velocity is a nice thing to have.

 

[Art Caputo]

My load in my Kibler Colonial. 100 yard, 3 shots. 1400FPS.

 

[Topsail]

30 years ago my hunting load was 140 gr 2f in a 36” 72 twist with 270 rb. Killed on both ends. Now it’s 90-100 gr. Target load is 70 gr.

 

[Grenadier1758]

The second edition of the Lyman Black Powder Loading Manual has tables of performance data on a lot of round ball data sorted by powder used and barrel length. The second edition can still be found.

Lyman Black Powder Handbook Loading Manual: All New 2nd Edition (midwayusa.com)

It may still be 20 years old, but the information hasn't changed.

 

[Howard Pippin]

I readily agree with hanshi. I've killed Two deer and one Antelope with 60 grains or a little less of 3F in my 50. I do try to stay at around 50 yards which isn't too hard as I used to archery hunt and 50 yards seems like a long ways. my flintlock is a one in 48, And I can't go over about 70 grains or seems to strip the rifling with a PRB. I possibly could with a tighter patch, but loading would get noticeably tougher.
Squint

 

[Sparkitoff]

Thanks for the great info! This one seems to be 1:72" ROT and is snug with a .570 ball and .018 pillow tick patch. Sticking to the original plan, I will try 80 Grains and see how she does, then tweak if necessary.

 

[Grimord]

Thanks for the great info! This one seems to be 1:72" ROT and is snug with a .570 ball and .018 pillow tick patch. Sticking to the original plan, I will try 80 Grains and see how she does, then tweak if necessary.

I have found that generally the slower the twist, the more powder needed to get the best accuracy. Doesn't always hold true, but has proven to be true in my rifles.

 

[mooman76]

I have found that generally the slower the twist, the more powder needed to get the best accuracy. Doesn't always hold true, but has proven to be true in my rifles.

I have heard that on more than one occasion and it actually makes sense.

 

[SDSmlf]

Thanks for the great info! This one seems to be 1:72" ROT and is snug with a .570 ball and .018 pillow tick patch. Sticking to the original plan, I will try 80 Grains and see how she does, then tweak if necessary.

Best way to know for sure. Have a couple of Bobby Hoyt rebores in 58 caliber (26” TC barrels) with 1-60 radius bottom rifling that really like 80-90 grains of 3F Swiss with a thick denim or canvas patch.

Generally for hunting, I sight in 2-1/2” to 3” high at 50 yards, then see where I am at 100 yards. Above load and guns are about 2-1/2” high at 50 and 2-1/2” low at 100 yards. ‘Right on’ at about 85. Almost 10” low at 125 yards.

 

[Herb]

Here is a comparison I did, .58 caliber 36 inch Green Mountain barrel (1-70 twist) and a Hoyt rebore, 24" 1-60 twist.

Another.

 

[nkbj]

.58 is a good compromise. It lets you shoot flatter and still have that anchoring characteristic so appreciated by us old guys. My .62 Hawken takes way much more powder and recoil to be shooting so flat and there aint no critters to justify it. Well, except for shooting at chipmunks.

 

[Sparkitoff]

UPDATE:
Taking all the advice above I started with 100-grains of powder. The rifle, a Zoli/Navy "Buffao Hunter" Zouave short rifle has a 1:72 ROT. I was conserving my BP for flintlocks and went with what is most commonly available around here, Pyrodex P. Using a .570 RB with .018 pillow tick patch cut at muzzle and 7:1 ballistol/water dry lube, the velocity is in the low 1600 FPS range. I traded for this rifle recently and the previous owner said he didn't shoot it and this was the first time out with it for me. First shot at 50-yards punched out the 12 O'Clock spot on the 8-inch round black circle using a center hold. The rear sight has a stepped elevator ramp adjustment, so I dropped it down a notch and it shot about 1.5-inches below bullseye. I'd rather be a bit high at 50-yards so I moved the ramp back up. Next shot touched the 1st shot at 12 O'Clock. Third made a triangular ragged hole out of the three shots. Moving to 100-yards, I had a 6-inch brown circle on white backing. Still using a center hold, the rifle printed three shots 4.5-inches low. The 3-shot group was a small "V" shape and 3" total with the bottom of the "V" being a dead center shot (but low). With open sights off a bench this is about all I can expect with zero experimentation. I'm pretty happy with the whole thing....rifle, load, accuracy, etc.

NOTE:
When I was a kid I got a Zouave from somebody's cellar and got around to using it in my 20's. I didn't know anything about it and just loaded what the gunsmith told me. I sat in a tree one afternoon and shot at a little buck. I missed, but it was a magical moment for me forever etched in memory. Somewhere along the way the Zouave got traded or gifted or something. I've been thinking about replacing it ever since and this was to scratch that itch. 30 something years later, I sat in a tree yesterday with the "Zouave Carbine". I relived the whole adventure, including missing a buck!

Thanks for the advice and tips as it paid off and saved me a lot of time and tinkering!