I need an expert on Civil War rifles and minie ball trajectories - would minie balls ever "tumble" in flight?

Question

A 2002 book on Civil War medicine written by a doctor states that conical minie balls fired from rifled muskets could tumble in flight. I think he is wrong. I can't imagine how - unless it was a freakish occurrence with the lower flange of the minie ball not fitting well into the rifling grooves. Minie balls should be spinning in my way of thinking, but I'm not a firearms expert.

Answer 1

The .58 caliber minie ball was notorious for tumbling in flight. The rifles from that period had a "slow" twist to them which imparted a "slow" spin to the bullet. The minie ball has a conical base (the bottom of the bullet was a hollow cone shape). This was done in order to expand the skirt and get a good seal between the bullet and the bore. If you put too much powder behind it the bullet will blow off a small portion of the skirt on the base as it exits the muzzle of the barrel causing the bullet to "trip" and tumble.

I owned a Zouave .58 replica musket and have stood behind someone else while they shot it with a high power load of powder. I could see the "sparkle" as the light reflected off of the bullet as it tumbled on the way to the target.

It wasn't long before I switched to a "modern" version of the minie ball (510 grains) with a solid base. It solved the problem.

Answer 2

Minie balls will tumble after hitting another object, such as a twig, because their velocity is slow compared to modern ammunition. Also, they are slightly smaller than the rifling in the gun barrel because they must be pushed through it by hand while loading the weapon. This is why a cotton patch is used, to tighten the fit so the rifling can do its job.. If the ball fits too loosely, it could tumble or "keyhole". And finally, most were cast by the user by hand using a hinged mold. If the halves of the mold do not match perfectly or the ball is removed from the mold too soon, and the ball is not properly trimmed of excess lead, the seams can affect the trajectory of the ball.

Answer 3

I am a former Army GRUNT & a light weapons specialist and have seen how this is possible. A lot of the military weapons in use today have ammo designed to tumble once it encounters resistance. I'm no Black Powder expert but, I would think that any round that hits an object has a possibility to do the same. It depends on how clean the rifles are kept, what debris, shrubs, weeds, etc.. that are between you and the intended target. I'm sure there were at least a few forward thinkers that designed their lead for this purpose. Any small pockets in the round would catch air and at that speed would create a spinning effect. It would be the same as a lopsided ball being thrown. Instead of straight-on penetration you would have a ripping and ricocheting action. With rounds like this you would theoretically be capable of multiple kills, or maybe a kill and a wounded. These are very effective tactics.

Answer 4

He is correct in a sense. Not all the weapons used were the more advanced rifled barrel guns. Some soldiers, particularly, Confederates were armed with smooth bore guns that did not impart the spin required to stop the projectile from tumbling, This made the weapons much less accurate beyond 100 yards. There were however, many troops armed with rifled barrel weapons which made them very accurate up to 300 yards. It was these weapons and the lack of understanding of the officers that made the Civil War the deadliest conflict in American history. Using antiquated tactics and frontal assaults led to thousands of deaths and a waste of manpower in many major conflicts.

Answer 5

Should not.......... unless it was the wrong diameter or worn lands in the barrel. Add to that a thing called "leading". When soft lead of the day was used, a little bit would come off and fill the grooves. After a good many shots, the goves will be be filled with lead and the rifle becomes a "smooth bore"

I have seen this happen when shooting cheap lead reloads in my 1911a . After about 6 mags of that stuff, acuracy goes nuts.

Remember uniform mass production was very early then.
The Wentworth rifle from England was one of the most accurate of its day but it had a special bullet mold for each rilfle. They were not interchangable.

Answer 6

Well it's my understanding, and I'm no expert either, that the bullet from an AK-47 tumbles and Aks are refiled also. Don't know about minie balls though. I once read, SAM magazine, the magazine that we would get when I was in the Air Force and they said that the AK was more destructive to the body, than the M=16, because the projectile tumbles in flight. At least that's how I remember it.

Answer 7

I cant see how they would tumble unless someone screwed up the rifling in the barrel or there was a problem with the ball.

Answer 8

Minnie balls were designed to fly straight and true. This improved accuracy tremendously. They possibly could tumble if one struck a hard obstacle at an an angle.

Answer 9

Not unless they richocheted off something first.