It occurs to me that I've used this term throughout the course of this thread without really explaining what's going on. What is it, exactly, and why do I keep saying "patched round ball only", and why would that even be desirable?
The patched round ball is an important part of our shooting history. It was the first widely accepted, practical projectile for both the smooth bored musket and the rifle as well. In essence, it's an undersized ball held in place in the barrel by seating it inside of a cloth patch. Again, a picture is worth a thousand words:
The above photo shows a patched round ball just being started in the muzzle. Notice it's not completely wrapped in the patch. The patch only has to go up far enough around the ball to get between it and the bore, so just over halfway up.
Like I said, the ball is undersized. I shoot either .530" or .535" dia in my .54 caliber rifles. My "standard" patch is .015" thick Irish Linen, which I have found to be tough enough to not burn through over heavy hunting charges. The rifle bore is a nominal .540" dia, and the rifling grooves run from .004" deep to .008" deep, depending on manufacturer. So, the patch takes up the windage between ball and bore.
The patch is lubed in any one of a number of ways. For just plinking, with light charges and when any load is going to be fired fairly soon, just plain old spit does a wonderful job. We just toss a patch in our mouth when we're dropping the powder charge down bore and it's good and wet and ready when we want to load the ball.
For hunting, when we're going to carry the thing around for awhile, spit will dry out. Or, if it's really freaking cold, it might even freeze. Neither is conducive to accuracy. So, we substitute some form of grease or oil. Back in the day, bear grease and sperm whale oil were the most prized for this duty. Today we use Crisco Oil or some brand of modern "wonder lube".
To speed things up a bit in the field, most of us use a "loading block", pre-loaded with extra patched round balls. Here's another 1000 words worth:
So, these are the original, "period correct" projectiles for use in these kinds of rifles. They are not without their problems, of course, and about midway through the 19th century were already on their way out. The militaries of the world were the first to drop them, due to the difficulties involved in maintaining any sort of a "rate of fire" with them. They simply get more and more difficult to ram down the bore as the bore gets more and more fouled. Tighter patch and ball combinations, when used with the lubes available back in the day, will prove well neigh impossible to get down the bore after as few as two or three shots. Not a big deal when hunting, we just swab the bore. Big, big deal when fighting...
So the militaries of the world came up with the first "improvement". Or, more specifically, a gentleman by the name of Minie' in either France or Belgium (can't remember which, so hopefully our Belgian shooter can help me out - Stijn?). Anyway, these are like a big airgun pellet, hollow on the bottom. They are so undersized that they will actually just drop freely down a clean bore. As the bore fouls we have to ram them home, but it never gets difficult. That hollow base then expands to grab the rifling when the charge goes off. Not nearly as accurate as other schemes, but certainly "good enough" when firepower is maybe a bit more important than accuracy. Oh, and that darn skirt will blow out if we try to load the charges that round balls will accept. In the Civil War, for example, these things were held to about 800-900 fps in an effort to not blow the skirts. Not really all that great for hunting.
