The Custom Loading .45 Colt

Guns Magazine, July, 2001 by John Taffin

From mild blackpowder loads to high-velocity numbers rivaling the .454, this good old "cowboy cartridge" proves to be one of the most versatile revolver loads around.

Even though the .45 Colt cartridge will celebrate its 125th anniversary very shortly, it is still our most versatile sixgun cartridge. There are few sixgun cartridges that can best it in any one category, and certainly none can do so as an all-around sixgun cartridge. It simply does it all.

Many of the detractors of the .45 Colt come up with the same old tired reasoning that it is a weak cartridge case, whatever that means. They would almost have us believe that cartridge manufacturers somehow have a section in their plant where they deliberately manufacture weak brass and the .45 Colt is the number one product.

Yes, the old balloon-head or folded-head .45 Colt brass originally loaded with blackpowder is weak compared to today's solid head brass found in the .44 Mag. case. Anyone using this argument, however, is at least 50 years behind times as solid head .45 Colt brass has been the norm since. 1952. Dick Casull did all of his experimenting that led to the .454 by using so-called "weak" .45 Colt brass. Those experiments began in the 1950s and should have settled thc weak argument right then and there.

Perhaps .45 Colt brass has been regarded as weak simply because of the early sixguns in which it was chambered. Frontier revolvers chambered in .45 Colt have almost paper-thin cylinder walls and should be treated accordingly.

From 1873, when the Colt Single Action Army debuted, it would be almost 100 years before we had a factory-produced .45 Colt revolver that was capable of even beginning to tap into the versatility of the 45 Colt. That sixgun, of course, was the Ruger Old Model Blackhawk chambered in .45 Colt, which arrived on the scene in 1971.

For several decades, loading manuals have had two sections for the .45 Colt -- one for the Colt Single Action and the other for the Ruger Blackhawk. This barely begins to touch the range of possibilities with the .45 Colt; however. There are at least six levels (with some overlapping) to be considered when attempting to create .45 loads. This means that loading this most versatile cartridge must not be approached light-heartedly. Knowledge of the capabilities of the sixgun being used is imperative as using the wrong load for the wrong sixgun can result in disaster.

Blackpowder Loads

Most of the .45 Colt revolvers manufactured in the 19th century were blackpowder sixguns. Colt changed from the screw holding in the cylinder pin to the spring-loaded latch system at serial #165.000 and many also take this as the change from blackpowder to smokeless in 1896.

However, Colt stated that they did not guarantee Single Actions under serial #180,000 for smokeless use. This gets us to 1899. To be safe, do not use any Colt Single Action under serial #192,000 (beginning in 1900) with smokeless powder.

Vintage Colt revolvers can still provide a great deal of shooting enjoyment. The original blackpowder loading was 40.0 grs. of FFg blackpowder under a 255 gr. bullet. Now there are many grades of blackpowder and we certainly have better primers now, but using old balloon head style brass and 40.0 grs. of Goex brand FFg, with a 255 gr. bullet in a 7 1/2 .45 Single Action results in a muzzle velocity of 1,050 fps. That is definitely a load to be reckoned with and also explains why they were able to kill such large animals as grizzly bears and buffalo with a sixgun even back then. This load was quickly dropped to 35.0 grs. for civilian use (875 fps) and 30.0 grs. for military use (800 fps).

Early Smokeless Loads

Even though these sixguns were and are designed to be used with smokeless powders, their cylinder walls are very thin by modern gun standards and should be loaded cautiously. For these sixguns we stay at 900 fps to 1,050 fps with 250 gr. to 260 gr. bullets. Favored loads with a Keith bullet from a 7 1/2" sixgun include 9.0 grs. of Unique for 1,000 fps: 10.0 grs. Unique for 1,090 fps; 20.0 grs. of H4227 for 1,085 fps (a great load); and 16.0 grs. of HS-7 for 1,065 fps. Any of these loads with their game getting Keith bullets are certainly adequate for deer and black bear sized critters at reasonable ranges.

Cowboy Shooting Loads

Vintage (replica and authentic) sixguns are also the ones most used in cowboy shooting activities. For these, we prefer a realistic blackpowder-style load and by the rules of cowboy shooting, we must stay under 1,000 fps. To keep within these parameters, we work up loads using a commercial cast 250 gr. RNFP from Bull-X or Oregon Trail running from 800 to 900 fps. A loading of 7.0 grs. of WW231 yields 800 fps; 6.0 grs. of TiteGroup yields 810 fps; 6.0 grs. of Red Dot runs at 835 fps; 6.0 grs. of N-100 runs at 870 fps; and 8.0 grs. of Unique yields 900 fps.

Transition Loads

New Frontier and S&W sixguns from the first half of the 20th century are only slightly stronger than the Colt Single Action, with the New Frontier being nothing more than the Single Action Army with a heavy top strap and adjustable sights. The New Frontier is also one of the most beautiful of all the single action models to surface in the last 125 years.