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Ball calibers and diameters make no sense.

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I am in the process of getting an answer from the NRA Questions & Answers. I ask them when the change occurred between the lead balls per pound, the two digit caliber system used by many of our muzzle loading military rifle/muskets, and the black powder caliber designations. I sent the letter about six weeks ago, so I should be getting an answer soon. When I have an answer, I will share it with the forum. I had a historian tell me that to answer the question you must go back and look at the time period and what was available at the time as far as tools and education. I think the government arsenals would have the best opportunity to have the tooling and education for better guns. Where as the back woods gunsmith would have limited tooling and education to make more precise gun and interchangeability. The back woods gunsmith did make every good guns but were not interchangeable with other guns made by the gunsmith. I am also trying to find out how the gunsmiths made a perfectly round ball at certain weight. Everyone say a ten ball bore but how good was the weighing of the material and how did they pull that into a perfectly round ball. Remember the back woods gunsmiths had very limited measuring tools. The hand held micrometer had not been invented yet. When I find out, I will let the forum know.
I have a cap & ball revolver in 44 caliber. I know what you are talking about. I will add, I try to get an even cut on the ball when I seat it. If that cut is not even all the way around, the ball will fly off course. I am waiting for the answer from the NRA. I think it will be interesting. Have a good day.
Gauge designations are the number of balls of that diameter it takes to equal a pound, but some shotguns are overbored so they aren’t all the same. .410 shotguns are the exception.
Cartridges are completely nonsensical and can be called whatever the maker wants. The 256 Newton for example is a 6.5mm and uses a .264 bullet. The 225 Winchester uses a .224 bullet, so why 225? The European stuff at least makes some sense.
The modern cartridge system has NO system at all. They can be named any one of various ways. The Europeans did it right by using the diameter of the bullet and the cartridge length in millimeters with R if it is rimmed. The fouling piece later called the shotgun did use the balls/pound system even to modern times as shotguns. This system went from 1 to 50. After the fifty gage the system become crazy so we went to a caliber system (0.410). When the hand held micrometer was invented, the lettered gages come into use starting with "A" (2.000). The military muskets (Brown Bess 0.75 caliber) went to rifle/musket (Springfield 1861 0.58 caliber) with rifling. Finally when the older models of rifle./muskets were out of the picture, we went to rifles with a receiver and separate a barrel (Springfield 45-70). The black powder designation (45-70) was used to the 20th century where our modern caliber non system come into use. The 45-70 caliber designation is still used today.
I do not know. If you do not have micrometers, take the cylinder to a machinist for measurement. One thing I have noticed is the chambers can be egged shaped (not round). Maybe you have noticed flash over between chambers in a revolver. This flash over can happen with an out of round chamber of a couple of thousandths. This can be quite exciting for the shooter when this happens. This is why the balls are cut when being seated in the chamber. Things are not perfect and the shooter must put grease over the chamber or felt pads between the powder and ball to prevent flash overs. I was a part time range officer for twenty years and seen several flash overs or ring fires on the firing line.
My black powder space in my gun closet is getting clogged with boxes of different balls of multiple calibers whose diameters for calibers seem to make no sense. For example, I have .44 caliber balls of 0.454 diameter for my cap 'n ball revolvers, and .45 caliber balls of 0.445 diameter for my flintlock rifles. Not to mention I have .36 caliber balls of 0.375 diameter for my 1962 Colt revolver and today got a box of .36 caliber balls of 0.350 diameter for my Le Page pistol. Confusing, to say the least, and doesn't seem logical. If anyone has a link to a good article or video that explains how this all came about and reasons for it, I'm all for some climbing the learning curve. Thanks!!
Calibers first…

A rifled bore has a major diameter (bottom of groove to the bottom of the opposite groove) and a minor diameter (top of a land to the top of an opposite land). When muzzleloading shooters and gunsmiths speak of bore diameter, we mean land to land, or the minor diameter. Bore diameter of cartridge guns is the groove diameter, i.e. The major bore diameter, bottom of groove to bottom of groove.

The easiest way to make sense of this is to think of a .44 caliber Colt or Remington percussion Army revolver. People writing back in the day called these “muzzle-loading” revolvers and referred to them as such in writing, although technically they don’t load from the muzzle. These had a land-to-land bore diameter of .440”, so they were considered .44 caliber. Grooves in these revolvers were about .006” deep, so the groove diameter would be .452”. Balls or bullets for these guns pass through a forcing cone and “fill the grooves.” Anyway, if you put a cartridge conversion cylinder in that revolver, it becomes a .45.

There are charts showing the diameters of lead balls of various gauges, the gauge referring to the number of lead balls required to weigh a pound. A 32 gauge ball, weighing exactly half an ounce, would measure .526”. However, I believe in practical use this was an approximation. I’ve seen frequent mention of a “half-ounce trade ball” in the literature, yet the most common ball size in the traders’ inventories was 28 gauge, 28 balls to the pound or .550” diameter. I just recently read that micrometers were invented in the 1860’s, and it is unlikely that there were many of them on the frontier, so I believe it is likely that there was a lot of estimation and rounding off in the calculation of ball size and weight. We know that patched balls have to be under bore size, or of a smaller gauge than the rifle. It is sometimes hard to tell in the old-time literature whether a writer means the ball diameter or the bore diameter. The bottom line, though, is how it shoots.

Notchy Bob
Just to add to the confusion, in the early days of cartridge revolvers they used a heeled bullet so that they could simply bore the cylinders through and use the same diameter bullet. When they went to the inside lubed bullet the had to go to a smaller bullet to keep the same case. Example, a .38 heeled bullet case would need a .36 bullet to fit inside.
Ball calibers and diameters make no sense.

Of course they do.
However, over time, you have two different systems of name creation, one uses the barrel bore diameter, one uses the projectile diameter. Then you had a technology change, from muzzle loading to fixed cartridges, and the amount of powder was added to the names, BUT at the same time, part of the world changed it's measurement system from English to Metric. Finally, it became acceptable to use the name of the inventor, or another wording be it an acronym or arbitrary name.

It's not unique to firearms...,

When I translate a brewing recipe from say the 1730's..., I have to try to figure out is it Winchester Gallons, or Imperial Gallons, and convert over to modern American gallons, plus are they using the English standard measure for a Firkin of ale which is 8 Winchester Gallons, or the Dutch standard of 9 gallons for a Firkin of Beer, which then determines the size of the "Hogshead" which is referred to in the recipe. ??? I have found that just because the author talks about making a "hogshead of ale" he may be referring to the Dutch hogshead of 54 Winchester gallons, instead of the ale hogshead of 48 gallons. It does make a difference making a conversion to today's recipes for home use... 😭

Lots of change in the world. When I work at Boeing, they said the only thing constant is change. I always tried to keep an open mind and be willing to accept change especially from the younger people. I tried NOT to use the words "I know because I am older and know more".
I have a copy of Lyman's Black Powder Handbook & Loading Manual on page 145 there are dimensions for revolvers. The 44 caliber shows chamber diameter of 0.448", bore diameter of 0.440", and groove diameter of 0.448" for a 8" barrel and 0.465" for a 9" barrel. I wrote Lyman about another caliber awhile back. Lyman said these were the dimensions from test guns used to make this manual. Lyman said other guns should be close. Unfortunately we do not have a web site for black powder like we do for smokeless powder guns. I am sure the manufactures talk among themselves to keep the interchangeability between guns. There was NO mention of brand name with the dimensions. Have a good day.
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I don't do safes. They're not big enough. I have two whole closets that have been safed and securitized and used to safely and securely store just the firearms. The ammo is stored separately under like safe and secure conditions on a totally different floor. What I really need is a whoie new house located in a free state, not some friggin metal monster gun safes!! Sorry.
A few more of those come onto the market down here every time we get another big storm, and we're PROUDLY about as free a state as exists anymore!
(As a many-generation Florida Native... in both senses of the term..., I don't generally hold with inviting more folks in, but can always use another ML-er down here, so I do make the occasional exception... )Just ðo some studying on multiple-hit areas to avoid, and stay at least 15 miles in from the coast and away from any tidal rivers!
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