Calibers of Original, 18th Century Rifles

[SOLANCO]

Perusing Shumway's "Pennsylvania Long Rifles of Note". Looking through "Masterpieces of the American Longrifle". Thinking back on shows and exhibits I have attended. The caliber of the rifles is never mentioned. I had wondered what the most popular calibers were in the 1700's. Now I am thinking there was no caliber standardization, except maybe in military contracts.
A builder on the frontier may have made barrels according to the diameter of a mandrel he hammer welded around. Or purchased barrels imported into Philadelphia and Baltimore from English makers. Or from makers in Philadelphia and Baltimore.
How much caliber standardization was there? And, if there was, what were the favored calibers?

 

[tenngun]

No standardization at all. Imported blanks or home made had to be reamed and rifled. But, standard sizes were in the base, so guns tended to be close. And it thought they tended to shoot looser fits, I don’t know that that true my self but often argued.
European rifles tended to be larger bore, and American rifles followed suit. Most early seem to be over .50 and could well be up to .62.
By the revolution smaller was coming in style. One British officer reported 7/16 was as big as he ever saw, about .45.
Guns were also freshened, rifled and reamed as needed, so it’s hard to say x gun was such and such caliber when made.
However I THINK what we see is what it was

 

[rich pierce]

Dan Phariss did a study and has posted it when this topic recurs. Hopefully he will chime in. Insofar as standardization, it’s hard to tell. I had to recut an original barrel that was about .35 caliber when I started freshing it, to about .375 to get the pits out. So some barrels may have been 2 calibers smaller when made.

Few rifles from the 1770s and thereabouts were below .42 caliber from what we can tell, and barrels in the .50-.54 range were common then. Some larger, but not so many.

 

[rchas]

Isaac Weld wrote "Travels through the States of North America and the Provinces of Upper and Lower Canada, During the Years of 1795, 1796, and 1797". On page 117, he notes: "The rifled barrel guns, commonly used in America, are nearly of the length of a musket, and carry leaden balls from the size of thirty to sixty in the pound. Some hunters prefer those of a small bore, because they require but little ammunition ; others prefer such as have a wide bore, because the wound which they inflict is more certainly attended with death ; the wound, however, made by a ball discharged charged from one of these guns is always very dangerous.'

So; approximately .54 to around .44. Weld makes no mention of any kind of standardization with rifles. I think the only standardized bores were those barrels made for military or trade arms.

 

[dave_person]

Hi,
I collected data on colonial, Rev War, and early Federal period rifles published in books for which the calibers were listed. I made sure these were rifles, not smooth rifles and not guns bored smooth later in their service lives. However, there was no way to separate out those that were freshed and rifled again. I had roughly 50 rifles in my sample. Bores ranged from 0.41" to 0.69" with an average of 0.52". The standard deviation was about 0.03" so 67% of the rifles were between 0.49" and 0.55", and 95% of the rifles were between 0.46" and 0.58".

dave

 

[SOLANCO]

I can see where getting the correct round ball might be an adventure.

 

[Pukka Bundook]

A mold was usually supplied along with a new gun.

What happened with second hand we can only guess!

 

[Uncle Miltie]

No standardization at all. Imported blanks or home made had to be reamed and rifled. But, standard sizes were in the base, so guns tended to be close. And it thought they tended to shoot looser fits, I don’t know that that true my self but often argued.
European rifles tended to be larger bore, and American rifles followed suit. Most early seem to be over .50 and could well be up to .62.
By the revolution smaller was coming in style. One British officer reported 7/16 was as big as he ever saw, about .45.
Guns were also freshened, rifled and reamed as needed, so it’s hard to say x gun was such and such caliber when made.
However I THINK what we see is what it was

Excellent answer.

 

[Loyalist Dave]

Perusing Shumway's "Pennsylvania Long Rifles of Note". Looking through "Masterpieces of the American Longrifle". Thinking back on shows and exhibits I have attended. The caliber of the rifles is never mentioned. I had wondered what the most popular calibers were in the 1700's. Now I am thinking there was no caliber standardization, except maybe in military contracts.
A builder on the frontier may have made barrels according to the diameter of a mandrel he hammer welded around. Or purchased barrels imported into Philadelphia and Baltimore from English makers. Or from makers in Philadelphia and Baltimore.
How much caliber standardization was there? And, if there was, what were the favored calibers?

Rifles of former times, were different from those of modern date; few of them carried more than forty-five bullets to the pound. Bullets of a less size were not thought sufficiently heavy for hunting or war.

So that would be > .457 but < .490. So I think he saw a lot of what we'd call .48 to .50 caliber rifles.

"Now," says the captain, “when you run your bullets, cut off the necks very close, and scrape them, so as to make them a little less, and get patches one hundred finer than those you commonly use, and have them well oiled, for if a rifle happens to be choked in the time of battle, there is one gun and one man lost, for the rest of the battle. You will have no time to unbreech a gun and get a plug, to drive out the bullet”
Notes on the Settlement and Indian Wars of The Western Parts of Virginia and Pennsylvania, from 1763-1783 by Joseph Doddridge

This second quote makes me uncertain...., are they loading with a thinner patch so a little "loose" or not?



LD

 

[Grenadier1758]

The only standardization that I am aware of is that the firearm had to function properly. Military arms were built in accordance with a specific pattern. Dimensions were not provided. The only requirement was that the finished product looked like the pattern and was pretty close to the same size and passed the inspections for suitability for use.

 

[SOLANCO]

"This second quote makes me uncertain...., are they loading with a thinner patch so a little "loose" or not?"

The captain seems to be advocating a little loose as preferable to a stuck ball. Interesting that he calls it "choked". I'd not heard that before but his meaning is clear.

 

[rich pierce]

"This second quote makes me uncertain...., are they loading with a thinner patch so a little "loose" or not?"

The captain seems to be advocating a little loose as preferable to a stuck ball. Interesting that he calls it "choked". I'd not heard that before but his meaning is clear.

Makes sense to call a ball stuck partway down the barrel, “choked”, though also new to me. Too bad we can’t just use the Heimlich maneuver.

 

[LongWalker]

Back when I was a teen, I looked at the calibers given in Kindig's Thoughts on the Kentucky Rifle. The average was a hair over .49". When RCA came out, I was going to do the same but never got around to it.

The original Dickert I borrowed for some shooting tests back in 2013 had a bore that mic'd just a bit over .484"; I shot it with balls that average .469" (old scissors mould, the balls were not perfectly spherical) and patches that mic'd .014". The Dickert has since been freshed, and I'm told is now "about" .51 (I've not had the opportunity to measure the bore since the work was done).

The only longrifles likely to be Revolutionary period or earlier that I have personally measured (N=3) averaged about .56", but that doesn't tell us what the original bore sizes were.

 

[longcruise]

I suspect many bare balls were loaded in a hurry in the heat of battle.

 

[ronaldrothb49]

Rifles of Colonial America and Thoughts on the Kentucky Rifle in the Golden Age are both good sources for the caliber of the rifles they picture. As others have pointed out there isn't any standards for the caliber, anything pretty much goes. If a gunsmith was making his barrels he would be limited to the mandrels and reamers he had if he even had more than one size. If purchasing from the local barrel mill of the importers then he was at their mercy with what was available. Today the barrel makers seem to have standardized calibers but back then anything in between what we consider as standard today shows up.

 

[Relic shooter]

Hi,
I collected data on colonial, Rev War, and early Federal period rifles published in books for which the calibers were listed. I made sure these were rifles, not smooth rifles and not guns bored smooth later in their service lives. However, there was no way to separate out those that were freshed and rifled again. I had roughly 50 rifles in my sample. Bores ranged from 0.41" to 0.69" with an average of 0.52". The standard deviation was about 0.03" so 67% of the rifles were between 0.49" and 0.55", and 95% of the rifles were between 0.46" and 0.58".

dave

Those of us who shoot mostly original muzzle loading firearms are for good reason folks who do their own casting & end up with a large selection of molds. As Dave states there was little in bore size uniformity unless they were military contract guns & those can be a bit iffy.

My all time favorite for hunting & competition rifle was an original 7 1/4 lb. Danish .70 cal. Jaeger. It's long range accuracy & knock down power made one shot big game kills easy. However I would not want to be an early soldier or hunter who needed to pack 100 round balls in the field for days & weeks. Perhaps they had ball-bearers
Relic shooter

 

[Belleville]

The principle of barrel making was to forge the barrel and then ream it. If the inclusions in the bore cleaned up the reaming was done, if not ream again. This is repeated until the inclusions cleaned up or the barrel thickness got too thin to be safe. Gunsmiths then furnished a mould with civilian guns. Early military guns were much made the same way but to nominal bore size and generous tolerances so that the ball size could be standardized. This is the reason that bore sizes very so much.

 

[LongWalker]

Don't forget the effect an outlier can have when calculating "average" bore sizes. I mentioned having seen 3 guns I felt were likely to have been made before or during the Revolution, and an average bore size of ~.56". One was .48", one was .52" . . . and one was .67". The .67 was rifled, the other two were in rifle configuration (patchbox, full-octagon barrel, etc) but bored smooth. (Although if I ever get the chance I'm going to run a bore scope down the barrels to look for signs of rifling.)

 

[brazosland]

Our idea of accuracy and theirs are very, very different. We are all accustomed to looking for small groups at the ranges where we want the gun to perform.

2” groups at 50 yards, 4” groups, even 6” groups will all kill a deer, or a man. None of us here would stand for a new gun shooting 4 or 6 inch groups. But, as noted above…the gun remaining serviceable during battle was much more important than a level of accuracy that would almost guarantee the gun would become fouled and unusable.

In my opinion, what made the top marksman of the day notable was that they had the knowledge and experience to know how to use patch thickness, and maybe a larger ball, to bring forth impressive levels of accuracy when required for competition or “sniping.”

As a marksmanship instructor at a very high level, I know that anyone can be a bad or average shooter even with good gear…but a great shooter can be so even with marginal equipment because he has the knowledge to make it perform.

 

[Jason holgate]

Great post