45 Colt Rifle Standard Pressure

Eighteen seventy three was an exciting year for small arms development with two notable guns being offered, including Colt’s legendary Single Action Army revolver chambered in 45 Colt and the Winchester Model 1873 lever-action rifle initially chambered in 44 WCF or 44-40.

While the former was immediately adopted by the U.S. Military, both found great favor with a variety of shooters that needed a reliable sixgun or rifle. However, many have speculated why Winchester did not offer their hugely popular 1873 leveraction chambered in 45 Colt, as well as their excellent Model 1892, which most certainly would have been very well received by shooters that favored the 45 Colt over the 44-40 and would have resulted in even greater sales. For that matter, why didn’t Marlin offer their excellent Model 1889 and 1894 leverguns chambered in 45 Colt? After all, it has now been more than 40 years since leveractions were first offered in 45: It began with the Winchester Model 94, followed by the Marlin Model 1894, Uberti Models 1860, 1866 and 1873 reproductions, various Model 1892’s made by Rossi/Puma, Miroku, Henry Repeating Arms and now even Smith & Wesson offers a Model 1854 levergun! So why can these rifles be chambered today but not during the heyday of lever-action rifles?

The reason that no leverguns were chambered in 45 Colt during the pre-World War II era was probably due to the cartridge’s rim, or lack thereof. Balloon head cases have not been produced since prior to World War II, so fewer and fewer shooters are familiar with their design. Essentially, the rim of most cases measured from .495 to .502 inch in diameter. When we cut that figure in half, the rim only protruded from the balloon head of the case around .010 to .013 inch. To make matters worse, period cases had no extractor slot as the post-World War II solid head cases did. (See photos.) The rims were just too small to work reliably in period leverguns. Post-war cases generally have a rim diameter of .510 to .512 inch (the latter figure being SAAMI specified), while the solid head measures .475 inch in most cases and cannot exceed .480 inch per SAAMI. This results in a more substantial rim that protrudes .016 to .019 inch from the solid head. And when we add in the extractor groove cutout, there is enough rim to obtain reliable function in leverguns.

During the post-World War II era, the popularity of the 44-40 continued to decline steadily (at least until cowboy action shooting gave it a new lease on life during the 1980s). However, the 45 Colt flourished and was chambered in many modern sixguns – both double and single actions. Clearly, there was a demand for a 45 Colt leveraction as a companion gun. Today leverguns chambered in 45 Colt are hugely popular and used for a variety of purposes including cowboy action competition, recreational shooting, hunting, home defense, etc.

Today’s discussion of handloading 45 Colt rifles is for standard pressure loads that have an industry maximum average pressure of 14,000 psi. It has been widely popular to handload the 45 to much higher pressures for greater performance in both “strong” rifles and sixguns. However, there are several rifles that should not be loaded with higher pressure loads, making standard pressure handloads the best place to begin. Nonetheless, for those wanting improved performance, loads will be offered with similar ballistics as a 44 Magnum revolver that pushes a 240-grain bullet to around 1,200 to 1,300 feet per second (fps), which has a good reputation for taking big game. However, we will duplicate those ballistics while staying within industry pressure guidelines and offer loads for cowboy action shooters or plinkers wanting low recoil and modest muzzle report.

As can be seen in the accompanying chart, factory loads from Winchester, Remington, Federal Cartridge, Hornady, Black Hills, Buffalo Bore, Magtech and Aguila were checked for velocity. Most of these loads are loaded with fairly fast-burning pistol/revolver powders and fail to reach potential velocities. In other words, going to slower burning powders can offer higher velocities without producing higher pressures, but that is part of the advantage of handloading ammunition to maximize performance.  

While the industry maximum overall cartridge length is listed at 1.600 inches, many rifles (and most sixguns) will accept cartridges that exceed this figure. And many excellent bullets are designed to be seated to exceed that length. The problem is that many rifles will not feed cartridges that exceed SAAMI specifications. For example, guns manufactured by Uberti, Miroku and Henry Repeating Arms that are based on the King patents such as the 1860 Henry, 1866 Yellowboy and 1873 Winchester will generally only feed cartridges that are within 1.600 inches or less. Winchester Model 1892 replicas from Miroku and Chiappa generally only feed industry spec cartridges. However, recently manufactured Rossi 92’s will feed cartridges up to 1.695 inches, but early production guns will not. Regarding the Marlin Model 1894, Henry X-Model and the Smith & Wesson Model 1854; they feed cartridges up to 1.700 inches, which makes them suitable for any loads in the accompanying table.

To develop the accompanying data, a Marlin Model 1894CB Cowboy Limited Carbine 45 Colt with a 20-inch barrel was used as the primary test vehicle. This rifle is fitted with a Skinner aperture rear sight and has offered respectable accuracy with a variety of loads and bullet styles. A second Marlin Model 1894 Cowboy (likewise with a Skinner aperture sight) with a 24-inch barrel was used to test the most promising loads for accuracy. The twist rate for both rifles is 1:38. (Note: At one time, Marlin listed the 45 Colt with 1:16 and 1:38 twist barrels; however, I am certain that the 16 twist was a typo.) Regardless, these rifles will stabilize bullets from 200- to 300-grains. For reference, Henry and Uberti rifles have a 1:16 twist, Smith & Wesson Model 1854 a 1:20 and Winchester/Miroku rifles feature a 1:26. Incidentally, when the 45 Colt is loaded with standard pressure loads, the velocity gains with barrel lengths over 20 inches is very modest, or just a few fps per inch of barrel.

New Starline cases were used to develop data. It might be of interest that Starline cases tend to offer less pressure than many other cases and often give a bit greater velocity, however, all Pet Loads data can be used in any modern, solid head case except where noted.

A Redding Dual Ring Carbide die was used to size cases that works the brass less and extends case life. If cast bullets sized to the standard diameter of .452 inch are going to be loaded, an expander die that measures .449 inch should be used to achieve proper bullet-to-case fit. However, when using soft-swaged lead bullets, an expander measuring .450 inch will benefit accuracy. Incidentally, most rifles will feature a groove diameter of .450 to .452 inch. Both jacketed and cast bullets that feature a crimp cannelure or crimp groove should receive a heavy roll-crimp that serves to keep bullets secure while being inserted into tubular magazines and helps powders to ignite properly. Jacketed bullets without a crimp cannelure (and are designed for the 45 ACP) should be taper-crimped.

Cast bullets are generally the preferred choice for standard pressure 45 Colt loads. Their advantages are many, including producing very uniform velocities (with correct powders) and higher velocities than a comparable weight jacketed bullet (pushed with an identical powder charge) and a long barrel life. In addition to costing less, especially if cast at home, they are very unlikely to stick in the bore with any reasonable load. If a rifle will feed a variety of bullet profiles such as the Marlin Model 1894, Henry X-Model and Smith & Wesson 1854, various Keith-type or LBT flat nose bullets can be used for hunting that are very effective without the need to expand. Many commercial cast bullets feature a BHN of around 18 to 20, which generally works fine. However, bullets cast with an 11 to 14 BHN cost less and often give better accuracy at typical standard pressure 45 Colt velocities.

A few notable cast bullets include the Rim Rock Cowboy 250-grain RNFP “old style” that features less beveling on the base and is a widely popular bullet for plinkers and cowboy action shooters. The 260-grain Lyman 452190 is a classic, as it is based on the original Government design and has proven very accurate. Since there is no crimp groove, it must be crimped over the ogive, so it’s important to get a proper case-to-bullet fit (use a .449-inch expander ball) to prevent bullets from deep seating into the case while in the magazine tube. The 265-grain bullet from RCBS mould 45-250-FN is similarly profiled as the Government bullet but features a front driving band. It can be crimped over the front driving band for an overall cartridge length that allows it to work in all rifles, but it can hang up while feeding in some Model 1892 pattern rifles. I generally crimp it below the driving band for a COAL of 1.642 inches and use it only in rifles that will accept longer than industry cartridges. In this application, it shoots remarkably well in rifle and sixgun! The original Lyman Keith mould 452424 at 260 grains is a classic, but in my experience some guns will shoot it very well while others are mediocre at best. The 275-grain Hunters Supply Flat Point is a very good bullet that shot well in both test rifles.

The meplat measures around .335 inch, which makes it an excellent choice for hunting big game. Another heavyweight bullet includes the RCBS 45-270-SAA that typically weighs around 285 grains depending on alloy. Using 9.6 grains of Hodgdon Longshot powder reached almost 1,200 fps, making it a capable hunting load at respective distances. For those that want expansion from cast bullets, the 260-grain Rim Rock SWC-HP with a gas check is a great choice, as it is cast fairly soft and when pushed to over 1,200 fps using Alliant Power Pistol, Hodgdon CFE Pistol or Accurate No. 5 powders and expands reliably. It has an overall length of only 1.575 inches and can be used in any rifle. Again, this is similar performance as a 44 Magnum revolver and is a worthy field load.  

Swaged lead bullets can give good results; however, I try to keep velocities at 900 to 1,100 fps to prevent barrel leading. Remington used to offer (through Midway USA) their classic .456-inch, 250-grain roundnose with a small flat point (often referred to as the Government bullet) that is pure lead and features a hollow base to obturate when fired in revolvers with generously large throats. However, in rifles, this bullet will give better-than-it-should type accuracy! During some recent extensive accuracy testing (prior to doing this Pet Loads project) using more than 20 different bullets in several rifles chambered in 45 Colt, few bullets were offering as good of accuracy as the old Remington bullet at 200 yards. Hornady also offers their cold-swaged, 255-grain swaged lead FP Cowboy bullet in .454-inch diameter that has produced good accuracy with velocities up to 1,100 fps. The 250-grain Speer SWC has also given good results and boasts of the popular SWC design.

This brings us to jacketed bullets. Hornady, Nosler and Speer each offer 250-grain XTP, Sporting Handgun JHP and Gold Dot HP bullets respectively, that are designed to expand at velocities of around 800 fps. The problem is that many powders are unable to push them much above 800 fps, and some powders cannot even reach 800 fps while staying within SAAMI pressure limits! On the other hand, the same powders can easily push 250-grain cast bullets at 900 to 1,100 fps or more. This is due to cast bullets having much, much less resistance as they go down the barrel. Many popular powders, including Alliant Unique, could only push these bullets from 850 to 900 fps from a rifle barrel. At such modest velocity, down-range expansion becomes questionable. If loads are also to be used in sixguns, performance is dismal at best. To obtain respectable performance, powder selection becomes critical. Examples include Hodgdon Longshot, CFE Pistol, Winchester AutoComp, Vihtavuori 3N37, and Accurate No. 5, which were all able to push the above 250-grain jacketed bullets to around 1,100 to 1,200 fps.

Another option is to use 230-grain JHP bullets designed for the 45 ACP, which due to their shorter bearing surface and lighter weight, can be pushed to notably greater velocities. Using the 230-grain Nosler Sporting Handgun JHP and 230-grain Hornady XTP, Alliant Power Pistol and Accurate No. 5 powders reached around 1,300 fps. As indicated, without a crimp cannelure, it is suggested to use an expander ball that measures .449 inch or smaller and apply a firm taper crimp that measures .465 inch at the case mouth, which will prevent them from deep seating in the case. Their accuracy and terminal performance is notably better than the various 180- to 200-grain JHP bullets that are also included in the accompanying Pet Loads data.

Another notable jacketed bullet is Hornady’s 225-grain FTX, which offers impressive terminal performance. Hornady offers it in their LEVERevolution factory loads that reached 1,071 fps from the Marlin test rifle. Due to the spitzer profile of this bullet, Hornady suggests trimming cases to 1.215 inches (as opposed to SAAMI specifications of 1.285 inches) for an overall loaded length of 1.650 inches. However, this cartridge length still exceeds SAAMI specifications and will not feed in many leverguns that are intended for industry-standard length cartridges. I elected to load this bullet in full-length cases for an overall length of 1.692 inches, which fed perfectly in both Marlin rifles, the Smith & Wesson Model 1854 and the Henry X-Model. This approach increased the case capacity and select loads reached over 1,200 fps and 75-yard groups hovered around 2 inches.

We have many relatively new powders that increase the overall performance of the grand old 45 Colt. Some offer new levels of velocity, but others offer outstanding accuracy by not being position sensitive (which is important in the big Colt case) and are super clean burning. While I might have my personal favorites of the many powders included in the accompanying data, it seems hard to find a load that does not offer good performance. For light target loads, Hodgdon Titegroup, Accurate No. 2, Alliant Red Dot and Bullseye are always great choices. Medium burn rate powders that offer higher velocities and good accuracy include Winchester AutoComp, Hodgdon Longshot, CFE Pistol, Accurate No. 5, Alliant Power Pistol, Vihtavuori 3N37, Ramshot Silhouette and True Blue.

For more than 150 years, the grand old 45 Colt has been offering a beautiful blend of accuracy, power and reliable performance in a variety of sixguns. Now it is enjoying huge popularity in leverguns, which are fun, accurate and capable field rifles.