Chapter 5 – Centaure Conversions the Next Level of the Evolution?

5.9 Thoughts about Ammo

 

5.9 5.9.1   5.9.2 5.9.3

Thoughts about Ammo Ammo for Colt Army Conversions, the 1871/72 Open Top and their Modern Clones Chamber and Rifling Groove Diameter Modern .44 Colt Cartridge

 

5.9.1

Ammo for Colt Army Conversions, the 1871/72 Open Top and their Modern Clones

 

Let’s talk about ammo for a minute! The diameter of the rebate segment of an original Colt 1860 Army cylinder or one of her clones is smaller than its forward area. We know this is due to the Army’s lineage from the 1851 Navy. That being the case how can you load 6 cartridges of .44 cal. into the chambers of an Army conversion cylinder?

 

5.9.1_1 Repro cartridge box used for .44 Colt rounds loaded with 200 gr inside lubed bullets over smokeless powder

 

The simple truth during the second half of the 1860s, the 1870s and 1880s, and today is this: If you objective is to stick to the original dimensions of a Colt 860 Army pattern conversion you need a .44 cal. cartridge with a rim that is smaller than what we are used today from the .44 Russian, the .44 Special or the mighty .44 Magnum, and surely smaller than the .44-40 or various .45 cal. revolver ammunitions available like .45 S&W or .45 Colt.

 

5.9.1_2 Comparative size of modern cowboy rounds (from left) .44 Colt vs. .45 Colt

 

This consideration led to the development and eventually the introduction of the good old .44 Colt centerfire (CF) cartridge. The round was officially adopted by the U.S. military between 1871 and 1873 for the Colt Army breech loading conversions. Later the more powerful .45 Colt of the Colt Single Action Army was phased in. However, at the western and southwestern frontier of the United States of A. the old .44 Colt round was a trusted and respected revolver cartridge for decades not only with the military, but also farmers, cowboys and the men of both sides of the law.

 

5.9.1_3 From left: Notably smaller rim size of .44 Colt compared to .45. Colt

 

During the early decades of the 20th century Colt breech loading 1860 Army conversions and the .44 Colt cartridge were widely used again. They saw action in the skirmishes and battles of the Mexican revolution between 1910 and 1929. The cartridge was manufactured until WW2 with black powder as well as smokeless loads.

Colt 1860 Army factory breech loading conversions and most of their field conversions altered at the frontier were chambered for this .44 Colt centerfire rounds.

The Long Cylinder Conversion (LCCs) of the Colt 1860 Army allegedly fabricated sometime after the end of the Civil War south of the Border (or in Texas) and the Colt 1871/72 Open Tops (OTs) were chambered for another .44 cal. round. These two breechloaders were chambered for the battle proven .44 Henry rim fire cartridge and its successor the Stetson .44 Henry. Back in the days this round was very popular and readily available ammo thanks to the 1860 Henry rifle and its successor, the Winchester 66. Colt 1860 Army type Long Cylinder Conversions and Open Tops could accommodate this ammo because they came with a specially made cylinder without the typical Army rebate. Their cylinders were straight, with an identical diameter at the front and breech side. The respective measurements are 41.2 mm/1.622 inch of the LCC and 40.1-40.5 mm/1.577-1.596 inch of the OT.

 

5.9.1_4 Outside lubed Western cartridge cut-aways (from left): .44 Henry RF vs. .44 Colt CF

 

Compared to the .44 Colt CF the .44 Henry RF were the more powerful round of the two rounds when launched from a revolver with proper sized 7,5” or 8” tube. Which was not the case back then. (see text further below) The .44 Henry deserves to be remembered for another important aspect only rarely mentioned in gun literature or books on the Wild West! Since you could load this round in the afore mentioned pistols and rifles the concept one type of ammo fits all was reality almost 10 years before the famous combo of Colt SAA Frontier Six-Shooter and Winchester 73 in .44-40 cal. hit the market in 1878!

As you can see on above picture these two traditional Western cartridges use outside lubed bullets of heel type. Case and visible bullet diameter are about the same. Consequently, boring-through a C&B cylinder for such cartridges was a simple and cheap affair since no special chamber had to be cut.

 

5.9.1_5, 5.9.1_6, 5.9.1_7, 5.9.1_8, 5.9.1_9 Sample of old .44 Henry cartridge boxes

 

The latter is usually needed when you are dealing with a round loaded with an inside lubed bullet instead, like modern big bore cartridges. Without a properly sized chamber you end up with a huge amount of overbore in the cylinder before the inside lubed bullet hits the forcing cone and engages the rifling. You literally have no seal.

 

5.9.1_10 Heel-type bullet and outside lubed .44 Colt cartridges (from left): Modern reload, original

 

Specifications and data of the two old cartridges are listed in below table. Left and center column shall serve as orientation only. Because during the 19th century their manufacturing was not such a standardized process as it is today. Hence dimensions and power would differ between their various cartridge makers but also from batch to batch.

 

Cartridges .44 cal. mm/inch	.44 Colt (traditional) outside lubed	.44 Henry Stetson .44 Henry	.44 Colt (modern) inside lubed
Cartridge length	37,54-40,25/1.478-1.585	ca. 34,16/1.345	ca. 38,00/1.496
Case length diameter neck diameter head	27,94/1.10 11,55/.455 11,60/.483	20,86/.821 + 22,9/.902 11,02/.434 11,20/.441	27,81-28,07/1.095-1.105 11,48-11,61/.452-.459 11,51-11,75/.453-.463
Rim diameter	12,30/.483	13,16/.518	12,49/.492
Bullet type diameter weight grain	heel 11,18-11,68/.440-.460 210, 225 + 235	heel 11,33/.446 200 + 216	no rebate (straight) 10,51-11/.413-.433 205 + 230
Powder grain black powder smokeless	21 yes	26-28 n.a.	yes yes
Primer	center fire	rim fire	center fire

Source: C.I.P., Erlmeier, H. A./Brandt J. H.: HANDBUCH DER PISTOLEN-UND REVOLVER-PATRONEN/MANUAL OF PISTOL AND REVOLVER CARTRIDGES, Starline Brass/Sedalia, Wikipedia

 

5.9.2

Chamber and Rifling Groove Diameter

 

One other observation regarding the venerable .44 Colt and the .44 Henry ought to be mentioned here. According to the research of the conversion guru R. Bruce McDowell the nominal rifling groove diameter of the vintage tube of the Colt 1860 Army was .451″. This indicates some .44 Colt bullets are very likely undersized: but, all bullets of the .44 Henry are definitively undersized. This further implies that neither energy nor accuracy potential of the rounds was fully utilized but gas leakage must have been significant. In accordance with our today’s understanding a close fit of bullet, chamber mouth and rifling groove diameter is desirable. What could have been the rational back then?

I found two groups of thoughts regarding this subject.

# During the years production, tolerances in the bore making of Colt 1860 barrels might have been considerable. Looking at the issue from this angle, undersized bullets are acceptable if you bear in mind that military tactics of the time suggested volleys instead of aimed fire. Now the statement function is more important than accuracy or as the Austrians put it the deterrent effect is considerable makes a lot of sense.

# Several U.S. collectors and shooters suggest undersized bullets were used as an additional safety measure to prevent bursting barrels. This comment applies to both the C&B type and conversion pistols.

To substantiate the latter thesis chamber mouth and rifling groove diameters of Colt 1860 Army C&B pistols of all 3 Colt generations, Italian clones of Armi san Marco, Armi san Paolo/Euroarms, Pietta, Uberti and the Belgian F.A.U.L. Centaures were measured. Please, be prepared for some surprising findings.

1. Chamber mouths diameters of all Colt generations and most of the Italians are smaller than their respective rifling groove diameters. The exceptions are Piettas of more recent production. The Pietta people seem to strive for uniform diameters.
2. The remarkably wide range of rifling groove diameters around the magic .451 found in Colts of all generations but also in the Italians was noteworthy.
3. The Centaures measured have a close fit of the diameters of chamber mouths and rifling groove diameters over the whole production period.

 

5.9.3

Modern .44 Colt Cartridge

 

The modern .44 Colt cartridge, see above table, right column, only has its name in common with the old one. Technically it is a .44 Special but .050″ shorter with a smaller diameter rim, same as .41 Magnum.

Particularly, re-loaders from the CAS fraction who are shooting by the 1,000s, rather than the 100s, like this modern .44 Colt round, yours truly included. Not only can you use readily available 44 cal. reloading components; but, the straight cartridge case design lends itself to be reloaded in today’s semi-automated multiple stations presses without messing up the equipment through the outside lubed bullets.

Today’s .44 caliber Colt Army conversions fabricated by Italian replica makers are chambered for this modern round. You can fire these .44 Colt rounds from pistols chambered for .44 Special or .44 Magnum, like a .38 Special will work in a .357 Magnum revolver. But not the other way round, please.

5.9.3_1 The War Dept. aka the best wifey of them all aka Cornelia engaging the steel buffalo at the Bar H Ranch in Clarendon, TX, with yours truly’s .44 Special Henry loaded with.44 Colt cal. smokeless ammo

 

Did you note my reluctance to comment on modern Army conversions in calibers other than .44 Colt? Admitting to my opportunistic semi-purism or strive for historical correctness I just don’t feel they are right even if they seem to work. I just love to shoot the smokeless .44 Colt rounds in my conversions, SAAs and rifles! This round is highly accurate, too, see the War Dept. above at the long range and at the short range below, too (2011 Annual Shoot of the Canadian River Regulators – bullet splitting contest).

 

5.9.3_2 2011 Annual Shoot Canadian River Regulators bullet splitting contest with cowboy guns

 

5.9.3_3 Winner used .44 Colt cal. Centaure Long Cylinder Conversion

 

 

Updated February 18, 2024

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