.58 calibre Springfield rifle musket.
By the time the smoke had cleared and the veterans headed back to their homes, the American Civil War (1861-1865)
had exacted a terrible human cost. In four long years of bloody fighting, half a million of the three million men
and boys in blue and grey had been wounded in combat. Two hundred thousand others had been killed. The cause of 90%
of the losses is said to be the minié ball. The two brothers in arms, the rifled musket and the minié ball, should
trigger one of the greatest changes of battle tactics of all time. Too many officers carried on the Napoleonic era
battlefield tactics and thus spilled the chances of obvious victories with the superior weapons. Also, poorly
trained recruits didn't have the knowledge to take advantage of the minié ball and rifled musket's deadly potential.
The ball is named after the French Captain Claude Etienne Minié who participated in the development of the ball.
The minié ball is a undersized conical with a hollow base made to slip down the barrel quite easily. Wrapped in
a paper cartridge which contained both the powder and ball it could be loaded at high speed without having to
literally hammer the bullet down the bore which was common when using oversized conicals and patched roundballs.
When the powder charge went off the bullet's sides, or skirt, expanded and made the bullet grip the rifling.
The result was a muzzleloading rifle with great accuracy that could be loaded at high speed.
Most original muskets have a special progressive depth rifling. The grooves were deeper at the breech area and became
shallower towards the muzzle. Usually .015" deep in the breech and .005" towards the muzzle. Unfortunately, very few
replica musket manufacturers rifle their musket barrels this way today. Parker Hale in Birmingham, England made Enfield
replicas with progressive depth rifling, but the machinery is now sold to Italy. I don't know if the quality of the
Italian replicas are as good as the Birmingham Parker Hales.
If you have a "normal" replica rifle musket you should be able to put 5 shots in a 1,5" group at 100 yards.
You should then pick a bullet that is about .002-.001" under the land diameter of the barrel. I'll use my
Armi Sport .58 calibre 1861 Springfield musket as an example: It measured .581" across the lands. Then I had
to have a minié bullet that had a .580" diameter. You'll notice that most of the moulds available has a diameter
that ranges from .575" to .578". If you need a larger diameter you'll have to special order a largerr one or
somehow enlarge the cavity.
Finding the Right Powder Charge
Lubricated minié balls.
If you have a minié ball of the right diameter you're on your way to get
some acceptable accuracy. Warning: the work of finding the best charge could
take ages! A charge of 55 grains can shoot great while a 56 or 54 grains
charge can open the group considerably. I use to start with a low charge
and build my way up with a .5 grain increasement. 2F or 3F? Well, it all
depends on what your musket likes. The original US charge was about 60 grains
black powder and the UK Enfield charge was 70 grains. I have never experienced
that a musket has performed well with at normal minié bullet with
charges over 80 grains. The reason for this is that the skirts get blown
which affects accuracy.
Start some place in the 35 grains range with 3F and 40 grains for 2F.
It could take some time before you get the 1,5" group at 100 yards,
but at he end it's worth it. Shoot from a bench rest and remember that
it doesn't matter where on the paper the bullets hit as long as they are
grouped. Sights can be adjusted later. I prefer to start the shooting
at 100 yards because some loads will shot great at 50 yards but lousy
at 100. Never a problem the opposite way though.
Another important factor to consider is the bullet lube. It's purpose
is to keep the fouling soft and lubricate the bore. Tallow and bees wax
was the original lube, and that also works ok today. My Springfield shoots
best with T/C Bore Butter. It is kind of sticky and slick, but I have
not found anything that works better. If the fouling gets hard it is about
time to consider a new lube. I use to feel with a finger in the bore after
each shot, and then the fouling should be soft. On hot, dry days har fouling
could be a problem, but if you wait a little longer between each shot
it should work itself out. Some like to put grease in the base of the
bullet, some do not like it. I prefer lube in the base, but not a single
gun likes the same thing it seems. Here are 5 points that you should follow to get the best accuracy with
a minié ball:
- Weigh your bullets to +/- one half grain.
- Weigh your powder to +/- .1 grain.
- Be consistent in what you're doing. Do everything exactly the same.
- Use powder and caps from the same lot.
- Cast your bullets from pure lead.