Cimarron Colt Cartridge Conversions (2023)



Cartridge firing big bore sixguns just did not happen overnight. Of three major sixgun manufacturers of the last century, Colt and Remington started with cap-n-ball sixguns later switching to cartridge firing sixguns. Smith & Wesson began producing a seven-shot single action pistol firing the .22 rimfire cartridge in the 1850's before the Civil War. Smith & Wesson's Rollin White held the patent on bored through cylinders that accepted fixed ammunition as opposed to the front loading Remington and Colt percussion sixguns. The Colts andRemington's were serious fighting handguns in .44 and .38 caliber while Smith &Wesson's were hideout guns in .22 and .32 rimfire chamberings.

In the 1860's Smith & Wesson had planned a top-break .44 caliber sixgun firing fixed ammunition but this project had to be put on the back burner until after the war. The first big bore cartridge firing sixgun with a bored through cylinder emerged as the .44 S&W American in 1870. It was chambered in .44 Rimfire, the same ammunition as used in the Henry Model 1860 and Winchester Model 1866 leverguns.

The United States Army, equipped with 1860 Colt cap-n-ball sixguns since the Civil War, decreed that the cartridge be changed to a .44 caliber Centerfire, the .44 S&W. Three years before Colt had their first sixgun firing fixed ammunition, Smith & Wesson received a military contract for 1,000, six shot, top break design revolvers.

During the late 1860's the Thuer Conversion was performed on approximately 5,000 Colt cap-n-ball sixguns. Thuer's invention altered the cylinder of percussion revolvers to allow a cartridge to be inserted from the front end. It was not tremendously successful.

Colt had thousands of parts on hand and the U.S. Army had thousands of sixguns in use that fired round balls that were seated after the powder charge was placed in each cylinder and then each nipple had to be capped. Richards' patent was used by Colt to convert cap-n-ball sixguns to the new fixed ammunition style. The Richards Conversion can be recognized by an ejector rod that sticks out behind the ejector rod housing about one inch. Remington conversions are also encountered and the backs of cylinders of Remington and Colts were cut off and a new section was fitted or a completely new cylinder was built to accept rimfire cartridges.

In 1872, Colt introduced their first big bore cartridge firing sixgun, which looks much like the basic 1860 Army cap-n-ball, as an open topped frame, .44 rimfire chambered sixgun. One year later The Peacemaker arrived. It took awhile but when they did it, they did it right. The classic sixgun of all sixguns, the Colt Single Action Army is still in production both by Colt and several replica manufacturers.

(Video) Cimarron's Richards 1860 Army Conversion

The Cartridge Conversions are an important part of sixgun history spanning the time frame between Colt's percussion revolvers and the Peacemaker, the Colt Single Action Army. This fact has been discovered to some degree by the movie makers and is starting to show up in more and more movies. Original Cartridge Conversions remaining from the 1860's and 1870's show evidence of being well used giving further evidence to their importance. We may live in a throwaway world but those inhabitants of the last century did not. Why discard a perfectly good gun when it could be easily converted to fire the 'modern' ammunition?Now the Colt Cartridge Conversions are being offered by Cimarron with both an 1851 Navy and 1860 Army version. Unlike the originals, these sixguns are for reasonable smokeless powder loads and black powder loads rather than for black powder only.

The original Colt Cartridge Conversions were chambered for rounds that used a heel type bullet, that is a bullet whose base was smaller in diameter than the rest of the bullet. This resulted in a bullet that was the same diameter as the outside of the case much like today's .22 rimfire rounds. To keep things simpler for today's shooters, the Cimarron Cartridge Conversions are supplied with the 1851 Navy using standard .38 Special loads, or .38 Long Colt loads which are available from Black Hills Ammunition.

The 1860 Army Conversion required the resurrection of an old cartridge, the .44 Colt in modern form. Today's .44 Colt is simply the .44 Special trimmed back from 1.16" to approximately 1.10". My fired cases measure 1.095". The diameter of the cylinder of the 1860 Army is too small to accept six .44 Special rims that have a diameter of .514" so the rims are also trimmed. My cases from Starline have a rim diameter of .487".

For loading the .44 Colt, .44 Special dies can be used if they have enough flexibility to neck expand and crimp. If they don't the bottom of each die can be trimmed accordingly. Today's .44 dies, most of which are designed to handle both .44 Special and .44 Magnum, will probably be too long for the .44 Colt.

The easier way is to order .44 Russian dies from RCBS and then one is set up to load both .44 Colt and .44 Russian. The standard shellholder for the .44 Russian/.44 Special/.44 Magnum is too large for the rims of the .44 Colt. The proper shellholder is RCBS's #2, or the same size as used for the .30-30.

I found that .44 Russian rounds from Black Hills worked fine in the .44 Colt 1860 Army and shot very accurately but only every other chamber could be loaded. Black Hills offers two versions of the .44 Colt, a 200 grain and a 230 grain load. These clock out at 700 fps in the Cimarron .44 Colt.

The original loading for the .44 Colt was 28 grains of black powder. In modern solid head brass, I used 25 grains by volume measure of Goex's FFg, FFFg, Cartridge, and Hodgdon's black powder substitute, Pyrodex in both the P and Select grades.

One has to be struck by the ingenuity of the gun makers of 150 years ago when these Cartridge Conversions are examined. The cylinders had to be altered or replaced by a cylinder with a loading gate and new breech face and a rear sight built into the top. The fact that they did all this without electricity or modern machinery is absolutely mind boggling to me!

(Video) Cimarron "Man With No Name" Conversion

The Colt Cartridge Conversions from Cimarron look, at first glance, like cap-n-ball sixguns until one notices the absence of a rammer to seat the round ball home and the addition of a loading gate and ejector rod for the entrance of loaded rounds and the exit of fired cases.

The test guns from Cimarron are the first into the country and as such have a couple of bugs that will be worked out. The 1851 Navy has a very smooth action but will sometimes get out of synch and the hammer will not cock. If the cylinder was then rotated slightly it would right itself. The problem seems to be a too long hand or a bolt that is not coming into place fast enough. Most, if not all, replicas are slightly out of time and need the touch of a good pistolsmith to smooth them up and adjust the timing.

With the 1860 Army it is simply a matter of poor inspection at the European end. The cylinder will have to be replaced as one chamber looks as if the reamer caught a piece of metal and then proceeded to drag it along during the chambering process. The walls of that chamber is filled with circular cut outs. Cimarron will of course stand behind their product and replace the cylinder.

This bad chamber gave me a chance to test an old legend. We are told that the old time cowboys placed a folded up bill in one chamber of their sixguns for emergency purposes or as the last resort, burial fees.

I was more cautious and used a one dollar bill. I can say that if a sixgun was fired very much, especially with black powder loads, with a folded up piece of paper money in place in one chamber, the bill would be at least singed and more likely burnt up. In any case it reminded me which chamber was the bad one and also allowed an empty chamber, empty of a loaded round that is, to always be carried under the hammer.

I can say without reservation that the old time Shootists must have really had good eyes or else they relied entirely on point shooting. The rear sight is barely a dimple and it required a lot of concentration for me to use these guns by sighting in the traditional way. Both guns shot about 6" high and 2" left. The windage, and the poor sighting (by today's standards) arrangement can both be taken care of by carefully opening the rear sight notch with a file and also being careful to take the metal off the right side to bring the point of impact over. The elevation can only be addressed by a new and higher front sight. I find the shooting high no real problem once the windage is taken care of. I can compensate for one sighting problem but not both. The old time sixguns were usually much worse than this shooting much higher at close range.

Both Cimarron Colt Cartridge Conversions were test-fired with smokeless loads and black powder handloads. The accompanying table has the complete results. You will see that these sixguns are no slouch in the accuracy department. The 5" barreled 1851 Navy is destined to be a cowboy shooting sixgun as it definitely preferred the .38 Special Cowboy loads from both Black Hills and Winchester. These clocked out at 700 and 740 fps respectively and put five shots in 7/8" and 1 1/8" at 50 feet.

Switching to black powder I found I had a gun that bound up very quickly with conventional black powder but kept running fairly smoothly with Pyrodex. This is a common problem with single action sixguns. Long before the bore is fouled to the detriment of accuracy, the cylinder binds or in the worst case scenario, refuses to rotate. Seventeen grains of Pyrodex P in .38 Long Colt brass from Starline averaged 860 fps and shot into 2" at 50 feet. This is right with today's .38 Special loadings. My bullet choice for the .38 Long Colt is Lyman's #358212 round-nosed 150 grains lubed with Lyman's Black Powder Gold. Magnum primers are always used with black powder loads in this case being CCI's #550.

(Video) 1851 Navy Colt Cartridge Conversion ( Taylor's & Company)

With the 8" 1860 .44 Colt, Black Hills 200 and 230 grain .44 Colt loads go 1 1/2" and 2 1/4" at 50 feet for five shots, while their .44 Russian loading, also with a 200 grain bullet, will put five shots into slightly over 1" when using three rounds at a time.

No problems were encountered with black powder loads in the .44 Colt. Using RCBS's #44-200 FN .44-40 bullet lubed with Lyman Black Powder Gold and seated over 25.0 grains of Goex FFg yields a muzzle velocity of 770 fps and a five shot group of 1 1/4". The same amount of Pyrodex Select, by volume, raises the muzzle velocity to 839 fps and a group of 1 7/8". Not bad for such "old" guns and loads!

The 1851 Navy has the grip frame that eventually became the Colt Single Action grip with little or no change while the 1860 Army Conversion carries the longer and more comfortable grip originally found on the 1860 Army. Original Colt Cartridge Conversions were available with either grip frame. I would like to see some of the current replicas of the Colt Single Action offered with the longer 1860 grip frame which is decidedly more comfortable to use.

Thousands of old time shooters found themselves armed with perfectly good cap-n-ball sixguns when both Colt and Smith & Wesson brought forth their cartridge firing sixguns. Most of those first guns went to the military so it was a natural step for a cap-n-ball shooter to step over into cartridge firing territory by having his sixgun converted. It also saved him a good deal of money. In this day and age when money seems to flow so easily we sometimes forget that this was not always the case.

Cimarron's Colt Cartridge Conversions show that these old sixguns would have been highly prized by their owners. I look forward to the 1872 Open Tops and Remington Conversions that will be coming along shortly.

Cimarron can be reached at P.O. Box 906, Dept. AH, Fredericksburg, TX 78624; phone: (830) 997-9090. In addition to the Colt Cartridge Conversions, they carry a complete line of replica firearms including the Model P, Smith & Wesson Schofield, Remington 1875 and 1890, and New Thunderer as well as the 1860, 1866, and 1873 leverguns.

1851 NAVY 5" .38 SPECIAL


(Video) CONVERSION REVOLVERS! from Cimarron Firearms

Black Hills .38 Long Colt 668 1 3/8"
Black Hills .38 Special Cowboy 697 7/8"
CCI Blazer .38 Special 148 HBWC 711 1 3/4"
CCI Blazer .38 Special 158 RN 750 2 3/8"
Federal .38 Special 158 RN 732 2 1/4"
Hornady .38 Special 158 LHP 762 2 1/8"
Winchester .38 Special Cowboy 740 1 1/8"
3-D .38 Special Cowboy 704 2"


CARTRIDGE -.38 Long Colt
BULLET -Lyman #358212 150 gr. RN
17.0 gr. Goex FFg 679 4"
17.0 gr. Goex FFFg 799 2 3/4"
17.0 gr. Goex Cartridge 653 3 3/8"
17.0 gr. Pyrodex P 862 2"
17.0 gr. Pyrodex Select 784 2"

*All weights measured by volume

1860 ARMY 8" .44 COLT


Black Hills .44 Colt 230 689 2 1/4"
Black Hills .44 Colt 200 700 1 1/2"
Black Hills .44 Russian 210 717 1 1/8"


(Video) Cimarron Richards Conversion Type II

CARTRIDGE - .44 Colt
25.0 gr. Goex FFg 770 1 1/4"
25.0 gr. Goex FFFg 846 2 3/4"
25.0 gr. Goex CARTRIDGE 719 3 1/4"
25.0 gr. Pyrodex P 873 3 1/2"
25.0 gr. Pyrodex SELECT 839 1 7/8"

*All weights measured by volume



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