Centaure Long Cylinder Conversion (LC Conversion): Bob Millington’s (www.armsportllc.com) 3rd generation Colt 1860 Army Long Cylinder conversions in Dennis Adler’s book COLT SINGLE ACTION FROM PATERSONS TO PEACEMAKERS should have received more attention. Because this rustic and economical approach to convert 1860 Armies and 1861 Navies alike to cartridge firing pistols for the poor cowpokes back then looked like another interesting proposition for a conversion project. The assessment of the late Bruce McDowell that originals were probably made South of the Border after the Civil War and could be had with barrels shorter than 8” added to their desirability. Because this triggered the idea of having a pair of Centaure Marshals converted into Long Cylinder Conversions.

#12089 (left) and #12067 (right) – base pistols for Long Cylinder Conversions

Colt Army Long Cylinder Conversions of yesteryear were originally made for the .44 Henry RF but some were altered to shoot .44 CF cartridges once such cartridges became available. Typically their cylinders had no bolt approach notches.

Left are my Marshals #12089 and #12067 the candidates for the conversions. #12067 was selected because she needs “waynerizing” anyhow.

In addition to this

waynerizing this conversion project will accomplish another objective: It will be cool to use a pair of Centaure LCCs in Cowboy shoots instead of my Uberti Open Tops.

Incidentally, the LCCs back then had a many design features which are to be found on the later made Colt M 1871-72 Open Tops as well: they were made for the same .44 Henry RF/Stetson .44 Henry RF cartridge,

Original Colt M 1871-72 Open Top

most had just a thin back plate but no conversion ring. Like the OTs the LCCs also had a straight cylinder.

Contrary to the OTs however, their cylinders have the diameter of the large front portion of the C&B cylinder, whereas the OTs diameter is of the smaller rear portion. Quite

a few LCCs got a rear sight dove tailed on the barrel lug, again similar to the OTs sight which is an integral part of the barrel, however.

To accommodate the new cylinders the steps in the Marshal frames will have to be milled flat. Like the originals their loading levers will stay in place but have no more function. The LCCs do not have an integrated ejector. Actually, they don’t have an ejector at all. In a nutshell, therefore, you can call the Long Cylinder Conversions the poor man’s or economy version of the Colt Open Top.

Close-up of Mumme Uberti Remington Army conversion #24229

This time German toolmaker and master gunsmith Klaus Mumme of Königsbronn was trusted with the conversions. Klaus is a respected CAS competitor. His alias is Sliding Horse. At the July 2010 Centaure convention in Hofheim he finally applied for the FROCS membership which was granted July 20, 2010. He is now FROCS #77.

Mumme has many years of solid gunsmith experience with cowboy guns in general. He understands what it takes to make a reliably functioning cartridge firing pistol. I first met him 2004. Back then he altered my Uberti Henry 1860 rifle and an ASP Winchester 1873 carbine from.44-40 to

.44 Colt caliber. These jobs were so nicely executed that my pard and fellow FROCS #7 Bumble Bee asked him to give his ASP Winchester carbine the same treatment. More important, however, are Mumme’s credentials as “converter” from a more recent project: earlier in 2008 he converted my old 1971 production

Centaure Long Cylinder


Project Outline

Base pistols

Marshals 1st variation, 2nd sub-variation #12067 & #12089



Barrel marking



.44 Colt inside lubed (liner, .429 rifling groove diameter)

Ejector housing




Conversion cylinder

newly lathed, without rabate, engraved Texas cattle brands


altered Centaure, nose remachined with firing pin

Hammer stop

or back-plate screwed in front of recoil shield with guiding hole for new hammer nose

Rear sight

dovetailed and mounted on barrel, blued


step has been milled off

Recoil shield

cartridge loading channel cut into right recoil shield


Centaure (steel, with cut for stock)


Centaure (brass)


blued incl. Frame, hammer in the white

Uberti Remington New Model Army into a .44 Colt firing “factory conversion” without loading gate pictured above.

The cylinder for this Remmie conversion was lathed by the afore mentioned Bob Millington but Klaus fashioned a new octagon barrel with .429 bore, dovetailed the thin recoil plate and PC front sight into

place, constructed and fitted the period ejector assembly, and modified the C&B hammer with a PC firing pin to ignite the CF .44 Colt cartridges. The finish is blue with a traditional case colored hammer. Despite her age this Mumme Remington Army conversion is one sweet tack driver!

Klaus Mumme and yours truly discussing at ease the LCC project June 1, 2008

After a lot of discussions backwards and forward during the following months regarding technical details of the conversion project and finish it was finally agreed that these 2 Centaure conversions will be completely rust blued, no case colors whatsoever! Initially, my preference was nickel plating but this was dismissed. From the Centaure RM I learnt the hard way how difficult alignment of shiny sights in bright sun light can be.

LEAD Technologies Inc. V1.01

Step of frame removed, back-plate before contouring

LEAD Technologies Inc. V1.01

To be turned into 2 LCC cylinders…

LEAD Technologies Inc. V1.01

…LCC cylinder in the white

The newly made conversion cylinders of the LCCs are lathed from 1.7225-42 CrMo4-V320 steel. That is the same alloy Karl Nedbal uses for his conversion cylinders. They will be engraved with Texas cattle brands. When the conversions were finally completed sans rear sight, engraving and bluing in January 2010 they were presented to the Munich Proof house for proof testing. But there was an unexpected hold-up. The proof house slammed on the brakes. They felt not comfortably applying their stamp of approval for “design deficiencies”.

No loading gate needed: cartridges and empties are kept in place by the recoil shield…unless you cock the pistol aiming at the sun

Texas cattle brands engraved on conversion cylinder. Note re-bobbed hammer with firing pin

No, they were not worrying about the open top design. They smelled potential danger from a conversion without loading gate, preventing cartridges or empties from dropping out of the pistol during firing or blocking the action. They stuck to this position despite the fact that they had proof tested my above Remington “factory conversion” 2 years ago which does not have a loading gate either!

They only changed their minds May 12, 2010 (!) when the historical correctness of this type of conversion was presented through supportive printed evidence from Dennis Adler’s and Bruce McDowell’s books. No more discussion and the proof marks were finally applied.

Thanks, Klaus for your patience dealing with these worry warts.

Another important accomplishment was recorded with this project June 16, 2010: the BATF Bureau of Alcohol, Tobacco, Firearms and Explosives of Martinsburg, WV, confirmed that custom converted FAUL Long Cylinder Conversions in .44 Colt can be legally imported into the USA on a temporary base! One could also say an important US government agency recognized this project.

August 7, 2010: almost compled

December 5, 2010: mission accomplished!

Only August 7, 2010 I could take the first look at almost completed LCC #12089. Just a few finishing jobs are needed like cutting the dovetail on the breech end of the barrel to install the rear sight, test firing her and adjusting the sights to bring POA and POI together, and finally polishing and rust bluing the Centaures.

Stay with me when we are approaching the finishing line of this project!

December 5, 2010 after some 30 months the deed is done, the conversion of my new pair of CAS match pistols is completed. They were personally delivered by Mumme to my house. During the bluing process he noted that an even blue-black color of the originally high gloss polished steel of the Marshals could not be achieved. Not even after a second and third attempt. Now they have this antique like mottled look. I like it.

#12089 resting on Dennis Adler’s COLT SINGLE ACTION FROM PATERSON TO PEACEMAKERS: note dovetailed rear sight

During his test firing Mumme could establish that both pistols were shooting to POA at a typical CAS distance of 10 yards with very little spread. No tools were needed to drop the empties out of the cylinders.

The Mumme twins: mottled look of #12089 (top), #12067 (bottom) over bright & shiny Arizona!

Now the $ 10,000.00 question: is this Mumme Centaure LCC the ultimate CAS pistol for a cowboy portraying an early 1870 character? You bet and lots of style points are on the horizon! As a side note our FROCS & buddy Bumble Bee was pretty impressed by Klaus’s conversion job. He happened to be at my house with a few of his Centaures when Mumme delivered my new toys. BB was so hot that he through his RNMA 1st variation #11681 on the table to have her converted to…you guessed it … an 8” barrelled LCC! He plans to use her together with his 7,5” barrel Uberti OT as his main match pistol! According to Mumme this time the conversion will only require 3 months. He explained that by the experience gathered converting my Marshals, ha!

Sights of #12089

No loading gate. Note hole in hammer stop/back-plate for firing pin!

First work-out of my 2 Marshall LCCs took place December 8, 2010. Accuracy at CAS distances is OK by me but I need to get used to their short sight radius before I test them at longer distances like 25 and 50 meters. The objective will be to establish their accuracy potential but more importantly their long term reliable function.

First shooting impressions at 10 meters/11 yards: pistols cocked & fired as quickly as possible, aiming at the bulls eye…

…#1269 connecting slightly to the left and #12089 slightly to the right. Correction is easy with the drift adjustable rear sights.


WDN/December 9, 2010

© 2007 Wolf D. Niederastroth