How loose should minie balls fit?

I cast up a bunch of .54 Lee minie balls the other day and were trying them out in my Lyman.

They didn't group as close as my patched round balls and I was wondering if they are too loose. You can easily push them down the bore with very little drag, is that what a person should expect?

I was unable to recover any to see how well the rifling was engaging the bullet.

Minies should be .001 or .002 under bore size. Lymans have pretty deep rifling, may be too deep for a minie ball to seal the rifling. Rifles designed for minies have pretty shallow rifling.

They're supposed to go down easily. They were designed so they could be loaded easily and quickly during battle. Accuracy wasn't the big concern. They wanted volume of fire over accuracy.

They should be fired with moderate powder charges so the skirt isn't blown out.

I have the Lee oversize minnie mould and they still slide right down. I can throw rocks more accurately than I can get them to shoot.

I bought the Lyman minnie mould and it has a much thicker skirt. They go down easy but with the thick skirt I shoot them with 90 grains of 2F and they are extremely accurate.

HD

Thanks for the replies fellows, I will play around with the Lee molded bullets a little more, I never tried to many different powder charges yet, and if I can't get decent results I will try the Lyman mold.

I was thinking of getting a Bison tag this fall and was leaning toward the minnie balls for that.

I measured the bore diameter of my .54 GPR Lyman, it was .542. You might start there. I believe the dia for .54 minnie is .533-.537. I ordered an oversize mold .540 from Lee also. It shot much better. My barrel is a 1:32 twist shallow groove for conical bullets. The next step is to size the bullets to just under bore dia for best fit.

flinthead said:

Thanks for the replies fellows, I will play around with the Lee molded bullets a little more, I never tried to many different powder charges yet, and if I can't get decent results I will try the Lyman mold.

I was thinking of getting a Bison tag this fall and was leaning toward the minnie balls for that.

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If you're going after bison you might want to reconsider your bullet choice.

Lyman has a Plains Bullet mould that I think is just what you need for bison. I have it and they are real good shooters.

What rifle are you shooting?

HD

Both my Lymans are 1:42, a Trade rifle and a Deer stalker so I may not find a good shooting combination for them in minnie balls.

flinthead said:

Both my Lymans are 1:42, a Trade rifle and a Deer stalker...

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Both of those guns have a 1:48 twist.

flinthead said:

I cast up a bunch of .54 Lee minie balls the other day and were trying them out in my Lyman.

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Were you using pure lead or wheel weights?

Pure lead tends to fill the grooves more completely when fired due to it's softer material.

The minie was not designed for deep grooved rifles like yours. The best choice would be a maxi style bullet with 2 or 3 rings. I got some 2 ringed maxis a while back, not sure of grn. weight, but they load easier than the 3 ring and are significantly heftier than a round ball.

The minie should fit loosley. That is the way they are deigned but they need both a shallow groove and a faster twist rate than a round ball. I think you are having a seal problem and that is not at all out of the question for a minie. There is also the question about the alloy that you used. The minie needs pure lead in order to obturate properly. Wheel weights and most other alloys are just too hard to work properly.

One thing you might try is using a lubricated felt over powder wad behind your minie to help form a seal. You could even put a little cornmeal on top of the felt wad before seating the bullet. About a teaspoonful will be enough. If this doesn't get your rifle shooting the minies better, you just aren't going to get it to shoot minies better. There are better conical bullets out there, anyway.

I have done quite a bit of experimenting with mini's since I use them for deer hunting and am a retired tool and die maker and am able to make sizing dies to exact dimension. I have found the best accuracy with .001 clearance, rifling about .007 to .008 deep, a thin felt patch over powder( I know this is against some peoples theroy that the gas alone will expand the mini. If I am correct the early enfields used a wooden and then later a clay plug to expand the mini's. But I have found that it takes a lot of time to make the wooden plugs and they did not seem to help accuracy, the felt patch did. )The early CVA barrels with .002 deep "scratch" rifling while fairly accurate with prb do not stabalise a mini. The deeper (.010 t0 .012 ) did not seem to work as well as the mid range depth.I realize that my experiments with 45 caliber modern minis might not dirrectly apply to civil war calibers, as cast clearances, and shapes. And most people are limited to whatever depth of rifling they have, not having access to several different barrels.But I think it will give you some idea of where to start to try to improve your accuracy.

Unless you have fairly shallow rifling- and I suspect you don't-- you almost have to use an OP wad of some kind to hold the gas behind the MINIE ball. You can use felt wads- as indicated, or vegetable fiber wads( Walter's) or even a loose filler like corn meal, to seal the gases from cutting down those deep grooves and cutting the sides of your Minie balls. As long as the hollow base in the Minie is clean of GREASE, the fillers and wads should not stick to the hollow base. ( Some modern black Powder rifle cartridge shooters put a bore diameter piece of wax paper between the base of their bullets and the lube/wad combination they use between the powder and the bullet. The Wax paper keeps anything from sticking to the base of the bullet.)

flinthead said:

I cast up a bunch of .54 Lee minie balls the other day and were trying them out in my Lyman.

They didn't group as close as my patched round balls and I was wondering if they are too loose. You can easily push them down the bore with very little drag, is that what a person should expect?

I was unable to recover any to see how well the rifling was engaging the bullet.

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Minies need light powder charges unless the skirt is pretty thick. 60 gr of FFG or so.
I would not hesitate to shoot a buffalo with a 54 RB a friend has a 54 flint that has killed several.
The issue minie for the 58 Rifle Musket had .010-.015 clearance IIRC.
If you decide to use a bullet use something pretty blunt and not a minie or a Maxi ball. Both are pretty poor designs for hunting.
Check the bore fit of any conical to make sure it stays on the powder if the rifle is carried/shaken with the muzzle down.
Most will move to some extent.
Dan

Here's another factor. You don't say WHICH Lyman you're using. They come with different twist rates, depending on the model, and that's going to affect relative accuracy with mini's and RB's. If it's the Great Plains Rifle with it's 1:60 twist, you'll almost certainly get bigger groups from a mini than RB's, especially as the distance stretches and velocity starts to drop. Out of curiosity I tried mini's from my own GPR. Groups didn't look all that bad at 25 yards, opened up to 8" or 9" at 50, and wouldn't reliably hit the target paper at 100.

I should have stated both guns are 1:48 twist, ones a Deerstalker the other a Lyman Trade Rifle.

The felt wad sounds like an answer to initial gas sealing. I cast the minnies out of pure lead and they are very soft. I can't try the felt wads out until the weekend, my "range" is in the back yard and I can only get 50 yards so, I will have to go to my son's place where I can shoot out to 400 yards if I want.

Thanks again for everyones suggestions.

Huntin Dawg said:

flinthead said:

Thanks for the replies fellows, I will play around with the Lee molded bullets a little more, I never tried to many different powder charges yet, and if I can't get decent results I will try the Lyman mold.

I was thinking of getting a Bison tag this fall and was leaning toward the minnie balls for that.

Click to expand...

If you're going after bison you might want to reconsider your bullet choice.

Lyman has a Plains Bullet mould that I think is just what you need for bison. I have it and they are real good shooters.

What rifle are you shooting?

HD

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Totally agree. I used .54 great plains to kill my 2 year old Bison. It took two hits in the lungs and liver to kill it.

If your interested in keeping the minie from sliding too much you might try wrapping it with teflon plumbers tape. Works for me to keep them snug enough to stay put.

As the others have said your rifling is way too deep for a minie bullet. It is not your rate of twist that is the problem with the accuracy of your chosen weapon. It doesn't take much to stabilize a minie since they are a weight-forward design similar to a shotgun slug but not enough to be stabile without some spin. I shoot a 20+ year old EOA P53 Enfield that will still give me 3" or less groups off a bench at 100 yards and it was and still is built with a 1-78" twist rate. I also comepletly fill my bases with A beeswax/lard lube.

The teflon tape sounds like a good idea as well. I have several rolls of the very fine stuff.

There was a farm that used to raise buffalo commercially a few miles from my house. They used an old 30/30 winchester to kill them. One head shot always dropped them. Of course shooting in a coral is a lot different than hunting out in the bush. Its the Woods Bison we hunt here and they are smaller than the plains bison but still a knarley old beast.

I should mention that last week I was ordering some powder measures and a powder flask from Caballas. I also tried to order some hornady plains conicals in .54. The lady taking my order said conicals were a restricted export item that the US government would not allow to be shipped to Canada. I guess it must be some kind of post 911 thing to not allow 1850's military technology to be shipped to a foreign country!??