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History of 454 Casull Ammo
For those who love big bore revolvers, the .454 Casull (pronounced like KA-sool) is often a favorite. Longer than the .45 Long Colt and much more powerful, this ammunition spent more than half of its life as a popular wildcat, not becoming a standard, factory round until it’d been in the handloader arena for over 40 years.
When it comes to size, the .454 Casull ammo comes in a .45 Colt case that’s lengthened about .10 inch, giving the shell a length of 1.383 inches. The .452-inch diameter lead bullet sits in a .480-inch diameter straight-rimmed case, making the total cartridge length reach 1.77 inches.
Bullet weights are most commonly found between 240 and 300 grain (gr), and muzzle velocities approach 1,900 feet per second (fps) with energy at the muzzle exceeding 2,000 foot pound force (ft·lb).
The ammunition is loaded under a high pressure, and even uses a small rifle primer instead of a pistol primer. These cartridges can be loaded to a maximum pressure of 65,000 pounds per square inch (psi) and can create over 60,000 copper units of pressure (CUP) when fired.
When it comes to big bore ammunition, the .454 Casull, which was originally proposed as the .454 Magnum, significantly dwarfs the other three magnum cartridges (.357 Mag, .41 Mag, and .44 Mag), not just in size, but also in performance and power. And it’s this power that’s made the .454 Casull one of the most powerful handgun cartridges in the world, a wildcat that’s evolved into a heavy-hitting hunting round that can take down anything the American wild provides.
Development of the .454 Casull CartridgeIn 1957, Dick Casull, a gunsmith from Utah known for making wildcat cartridges, joined forces with Jack Fulmer and set out to develop a handgun hunting round that could not only take down any of North America’s large game, but also protect its shooter against any of the apex predators they may encounter while on the hunt.
Casull and Fulmer took the .45 Long Colt case and both lengthened it and thickened the shell’s wall, making it stronger and more durable. They filled this casing with a triplex load of propellants, starting with a quick-burning powder on the bottom, a slow-burning powder in the middle, and then topped them with the slowest-burning powder, using the compression from the bullet to keep the majority of the powders separate. This created a progressive burning that lead to a progressive acceleration of the bullet as it moved through the barrel. They then capped it with a bullet weighing 300 gr. When fired, the lead bullet blazed down range at 1,600 fps.
In November of 1959, Guns & Ammo writer P.O. Ackley gave the initial public mention of the newest, hottest wildcat, the .454 Casull – a powerful cartridge for large game and the first handgun ammo capable of taking the largest animals on the planet. It’s even been claimed that .454 caliber ammo has sufficient accuracy and energy retention to take medium-sized game as far as 200 yards out.
.454 Casull Ammo Acceptance by SAAMIAlthough .454 Casull ammo has been loaded and reloaded by people for decades, it wasn’t accepted by the Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI), the organization that sets and publishes the industry standards when it comes to ammo, as an official cartridge. It was simply too hot, with too much energy and too much power.
Finally, in 1998, SAAMI included the .454 Casull in its listing, taking it off the wildcat market and classifying it as an official ammunition cartridge, but not with some significant changes to ensure safety and reliability. By SAAMI standards, the .454 Casull must include:
• A small rifle primer instead of a large pistol primer, due to the thicker primer cup which minimizes flowback
• A thicker case wall to strengthen the whole cartridge
• A customized .030-inch thick jacket, necessary because the ammo’s cup is so high that without it, bullets could swell in the gap and create shavings of lead that could wear down the revolver’s barrel and frame
• A maximum pressure of 65,000 psi (even though most factory loads max out around 55,000 psi)
More:
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