Rifleman Q&A: Colt 1860 12-Notch Conversion

by
posted on August 20, 2025
** When you buy products through the links on our site, we may earn a commission that supports NRA's mission to protect, preserve and defend the Second Amendment. **
Colt 1860 12-Notch Conversion
Photos courtesy of Rock Island Auction Company.

Q. At a gun show, I saw a Colt 1860 Army Richards Conversion with 12 cylinder notches instead of the usual six. The dealer was not sure whether this was original to the gun. Were these extra notches a factory variation or just some frontier gunsmith’s backroom project?


A. What you saw was a rarity within a rarity. In 1871, Charles Richards patented a system that enabled Colt to transition from cap-and-ball to self-contained metallic cartridge revolvers utilizing Colt’s surplus Civil War Army parts. A new—albeit short-lived—safety system was devised to prevent the hammer from resting over a loaded chamber.

1860 cylinderPerhaps as an experiment, an extra “safety notch” was cut between each of the 1860’s cylinder bolt notches, making it a 12-notch gun. With the hammer brought to half-cock, the bolt, as before, would drop down into the frame. Then, with the user depressing the trigger while slightly pulling the hammer back before lowering it from half-cock, the bolt would rise up into the safety notch, securing the cylinder with the hammer resting between two loaded chambers.

Unfortunately, the 12-notch system seemed to be doomed from the start. It added to the conversion’s manufacturing costs, and the effectiveness of the safety notches depended upon a perfectly timed gun. Finally, the safety notches were falsely blamed for rupturing cylinders, as, in some instances, a small chunk of metal seemed to be “blown out” from the original cylinder notches.

Some incorrectly theorized that the new safety notches were the culprit. However, those notches were cut between the chambers—the thickest part of the cylinder. Conversely, the guns with “blow-out holes” show them at the bottom of the original cylinder notches, where the cylinders are the thinnest.

Nonetheless, the 12-notch system was discontinued. Of approximately 9,000 1860 Richards Conversions manufactured between 1873 and 1878, fewer than 120 factory 12-notch versions were produced, making them highly sought after today. Beware of fakes, though, as Colt also produced 12-notch cylinders for separate sales and, more recently, unscrupulous individuals have created spurious versions.

Latest

bluing with torch
bluing with torch

Tips & Techniques: DIY Fire Bluing

Is there anything prettier than fire bluing? This bright, “peacock” blue color is one of the world’s oldest firearm finishes and can be found on guns dating back as early as the 16th century and is still used on some of today’s high-end custom arms.

Rifleman Q&A: Eddystone Bayonets

"I recently started collecting World War I U.S. military firearms. I want to obtain a Model 1917 rifle made by each contractor—Winchester, Remington and Eddystone—along with bayonets for each. However, I can only locate bayonets made by Winchester and Remington. Why are bayonets made by Eddystone so hard to find?"

NRA Youth Education Summit 2025 Provides Scholarships, Leadership Lessons

The 2025 NRA Youth Education Summit (Y.E.S.) brought together 32 exceptional high school students from across the United States.

Unfair Advantage: The Walther PDP Pro-X PMM

The latest “Pro” model in this famous German maker’s line of U.S.-assembled pistols leverages more than 100 years of experience in building service-size semi-automatics. And the results are better than even most experienced shooters should expect.

The Armed Citizen® Sept. 8, 2025

Read today's "The Armed Citizen" entry for real stories of law-abiding citizens, past and present, who used their firearms to save lives.

Terminal Ballistics 101: What You Must Know As A Rifleman

It is easy to take a box of bullets for granted, but as a rifleman, it is important to understand all variables at play when it comes to terminal ballistics. This guide, from NRA Firearms Sourcebook, will help drill down on what is important.

Interests



Get the best of American Rifleman delivered to your inbox.