44 or 45? Colt replica history

[Tejicano Loco]

Back in the 1970's I bought my first revolver which was a non-historic 44 caliber "1851 Navy". At the time I looked around and found that a 0.445 round ball loaded perfectly - leaving a thin, lead ring shaved off when loaded into the cylinder.

Many years later I noted that there are cartridge conversions for "44 caliber" revolvers which are in 45 Colt. I know that the 45 Colt fires a bullet that is much too big to fit down the bore of the revolver I had back in the day.

In talking with a fellow gun enthusiast I was told that the Italian makers had reverse-engineered their products to fire a 44 caliber bullet while the original "44 caliber" Colt revolvers actually had bores that were about 0.452 inch diameter. We assumed that the original guns were referred to as 44 caliber because that was the size of the ball you would use with a patch in the guns made back then.

If the above is true I guess there must be a lot of replicas from 30-50 years ago which were made in the smaller 0.440 bore. I assume that current production replicas are now being made with 0.452 bores (or something very close).

Does anybody have more information on this subject?

 

[AntiqueSledMan]

Hello Tejicano Loco,

Yes, the Original .44 Colt shot a .451 diameter bullet, but it was used in a conversion revolver.
Keep in mind that the Modern .44 Colt is loaded with .430 diameter bullets, same as .44 Special and .44 Magnum.

The only ones loaded with the .451 diameter bullets are hand loaded like the ones I load myself.
They require a heeled base bullet, the base of the bullet is either cast or sized to about .429 diameter.

The reason for this is the fact that back in the day a 44 caliber was bored to .44" then rifled, which created the .452" groove diameter.
A little later in time the bores were standardized, .452 - .454 for a 45 cal, .429 - .430 for a 44 cal and so forth.

I do believe the modern Italian revolvers chambered in .44 Colt take the .429 diameter bullets,
where a true conversion from Cap & Ball will take the .451 or .452 diameter bullets, so the .45 Colt is a good fit.
Also the Italian manufactured Conversion revolver's chambered in .45 Colt are over-sized to allow the six .45 Colt cartridges to fit.

Early manufactures used what they thought a .44 caliber should be, the .44 S&W American was .434" diameter with a .412" Heel,
the .44 S&W Russian was a .429" diameter, the .44 Remington CF was a .447" diameter with a .428 heel, the 44-40 Winchester was a .427" diameter,
the .44 Merwin & Hulbert was a .422" diameter, I have the .44 Henry listed at .446" with a .423" heel, and of course the .45 Colt was .452" diameter.

As far as your revolver taking .446 diameter balls, I believe the theory is to shave a lead ring to create a good seal. After firing the ball will bump up to the diameter of the barrel. I'm not sure the barrel was .446", probably .452" as the new Pietta's cylinders are also .446" bore but the barrels are .452".

If this doesn't confuse you, I don't know what else can be said.

 

[rodwha]

^
This. They used to be measured by the lands whereas now we measure by the grooves.

https://en.m.wikipedia.org/wiki/.44_Colt

 

[AntiqueSledMan]

Hello rodwha,

Don't put to much faith in Wikipedia, lots of mistakes in your link.
One mistake that stands out is where they mention Colt boring through the percussion cylinder, Colt had to manufacture new cylinders for their 44 caliber conversion.
Even then the bolt notches broke through on many examples, the Colt cylinder was just not big enough for a large caliber cartridges.
There is a lot of confusion as to what caliber everything was or is, the Italians are just building what they think will sell, it's a profit game.
Even your statement of "They used to be measured by the lands whereas now we measure by the grooves" doesn't really explain it.
Example of a 38 Long Colt with a .375" bullet and a heel of .357" and a 38 Special with a bullet diameter of .357",
same diameter case so they used the heel diameter for bullet diameter and also changed the bore to fit. This is what they did with the .44's also.

AntiqueSledMan.

 

[rodwha]

Hello rodwha,

Don't put to much faith in Wikipedia, lots of mistakes in your link.
One mistake that stands out is where they mention Colt boring through the percussion cylinder, Colt had to manufacture new cylinders for their 44 caliber conversion.
Even then the bolt notches broke through on many examples, the Colt cylinder was just not big enough for a large caliber cartridges.

I’ve not delved into the history so much myself, but I’ve read of the existing cylinders being modified such as in this article:

https://www.guns.com/news/2012/12/13/the-cartridge-conversion-revolvers

As to the .38’s I assume they just kept the common name/caliber designation since the ~.375” grooves is a ~.38 caliber.

 

[Driftwood Johnson]

Howdy

This is an original Colt Richards Conversion revolver.

These revolvers were converted from percussion to fire cartridges.

Four original 44 Colt (not 45 Colt) cartridges are shown with the revolver.






The earliest examples of this model did indeed have percussion cylinders altered to fire cartridges. Later versions had new cylinders made up. Read McDowell's excellent book about Colt Conversions to verify this.






Basically, the rear of the cylinder, where the nipples used to be, was machined away, the chambers were bored through, and a new ratchet star was machined onto the rear of the cylinder.






A Conversion Ring with a loading gate was screwed to the frame to make up for the material that had been machined away from the percussion cylinder.






This photo shows the Richards Conversion cylinder on the right, and a modern Pietta 1860 Army percussion cylinder on the left to illustrate what had been machined away.






I have slugged the bore of this revolver. It is difficult to get an accurate measurement because the rifling has an odd number of grooves. It is much simpler to slug a barrel with an even number of grooves. Anyway, as near as I can tell the groove diameter of this barrel is .451. That is how modern barrels are measured, by groove diameter, not by the 'bore diameter', or across the lands.






The 44 Colt cartridge was developed specifically for this model of revolver. The cartridge was developed so the brass fit into the chambers of the percussion cylinders. The bullet was the same diameter as the inside of the chamber. In order to do this, a heeled bullet was used. The 'heel' was a slightly narrower section at the rear of the bullet that fit inside the brass, while the main diameter of the bullet was the same as the outside of the brass. Just like modern 22 Rimfire ammunition.






I bought a mold from Old West Bullet Molds to cast bullets for this revolver. As you can see, the heel of these bullets is slightly smaller in diameter than the rest of the bullet, and fits inside the modern Starline 44 Colt brass.






Later, when the 45 Colt cartridge was developed for the Colt Single Action Army, the rifling was still .451 in diameter. However by this time most cartridges used a bullet with the same outside diameter as the inside of the brass case.
Here is a photo of a 44 Colt cartridge on the left and a very old 45 Colt cartridge on the right. Notice the 44 Colt bullet is the same diameter as the case, the 45 Colt bullet is slightly smaller in diameter than the outside of the case.






I know nothing about the Italian gun manufacturers changing the rifling groove diameter when they first made reproductions of percussion revolvers. I do know that Aldo Uberti first started making reproductions of the 1851 Navy around 1959 or so, as the centennial of the American Civil War was approaching.

I bought this Uberti 44 caliber, brass framed 'Navy' in 1968. I do not recall slugging the bore, but I know I always fired .451 balls from it. These shaved off just the right amount of lead when seated in the chambers. You can see the Uberti trademark stamped onto the frame just below the cylinder, the octagonal muzzle of an 1851 Navy with a U inside. This is the reason that Uberti's first replicas were sold under the name of Navy Arms.






I bought this EuroArms replica of the 1858 Remington in 1975. Many years later I bought a 45 Colt cartridge conversion cylinder for it. This photo shows the revolver with the conversion cylinder.






Before buying the cylinder I slugged the barrel. A little bit tight for 45 Colt, it was .449, as opposed to .451, but it has always worked well when fired with 45 Colt cartridges loaded with Black Powder and .452 diameter bullets.


Anyway, I have always read that the old '44' caliber percussion revolvers were called that because the barrels were 'bored' 44 caliber, then when the riffling was cut the the grooves were of the larger diameter. Later we started using rifling groove diameter to define caliber, rather than the land diameter, which would be the diameter of the bored barrel before rifling.

 

[Tejicano Loco]

I really appreciate all the replies. Lots of good information here. I had not considered the groove diameter being so deep with the land diameter being only 0.44 or close to that.

I'm not sure what the differences in the cylinder bore diameters between the originals and the Italian replica I had in the 1970's. As that gun had cylinder bores that were 0.440 (or very close to that) there was no way to seat bullets with 0.451 diameter - so a groove diameter of that size would not have mattered in that gun.

I currently own a San Marco produced "2nd Model Dragoon" so I will take the above information and check the relevant dimensions to see what diameter bullet would make sense to shoot in that.

 

[rodwha]

The lands on my 2013 Pietta NMA are 0.442” and the grooves are 0.4525”. I never measured the chambers but they’re said to be 0.446” or so. Mine has been reamed to 0.449” and chamfered but I’m considering opening them up further, at least to .451”. Those chamber walls just seem a bit thin to me, though there’s a couple of guys who’ve claimed to go to .453” or more using energetic powders and bullets so their pressures should be pretty high too.

 

[Driftwood Johnson]

Howdy Again

From Jerry Kuhnhausen's The Colt Single Acton Revolvers, a Shop Manual Volumes 1 & 2:

From a US Ordnance document dated 1882:

Groove Diameter: .454 min., .455 max.
Groove depth: .005


Bear in mind that after WWII 45 Colt groove diameter was changed to .451 to match 45ACP groove diameter.

And that is why there are commonly two different diameter bullets available for 45 Colt; .454 for the pre-WWII revolvers and .452 for the post-WWII revolvers.

Anyway, those are the numbers from 1882.

I have slugged several of my 45 Colt revolvers, all slug at about .451 or .452 for groove diameter.

I have never bothered to measure land diameter.