I recently acquired a Ruger Super Redhawk Alaskan revolver chambered for the .454 Casull cartridge. For the unfamiliar, the .454 Casull is among the most powerful handgun cartridges in the world. It was designed in the 1950s by Jack Fulmer and Dick Casull. It is essentially a magnum-ized .45 Colt; the case is about 1/10 inch longer and is built to withstand considerably higher pressures (over 60,000 CUP in some loads). The bullets in a .454 are commonly in the range of 250 to 350 grains, and can attain muzzle velocities of 1900 feet per second (fps) from a handgun with sufficient barrel length.
The Ruger SRH Alaskan is a line of revolvers intended for use as personal protection in the company of large predators (like brown bears). The Alaskan is also the first revolver that puts the immense power of the .454 into a package that is small enough to wear conveniently while hiking, fishing, or engaging in other outdoor activities. Its 2 1/2 barrel is a full 2 inches shorter than any other commercially available gun that shoots the .454 (at least to my knowledge). Ruger went to great lengths to make the Alaskan compact and still strong enough to handle the .454, including the use of an innovative stainless steel alloy in the cylinder. The Alaskan is an engineering accomplishment weighing only 40 ounces. It is quite arguably the edge of the envelope when it comes to big boom in a small package.
Unfortunately, the edge of the envelope is not always a comfortable place to be. Lightweight guns that shoot very heavy ammunition are potentially subject to a host of issues that range from recoil that many people find unacceptable, to premature gun wear and/or failure, to a phenomenon known as crimp creep. It is this issue of crimp creep (sometimes referred to as “crimp jump”) that I recently experienced with the Alaskan.
Crimp creep refers to a bullet in an unfired cartridge in the cylinder actually being pulled forward in the case as a result of the recoil it experiences from the other cartridge(s) being fired. (Strictly speaking, it is probably more accurate to say that the bullet isn’t pulled forward, but rather it resists being pulled back with the rest of the cartridge.) The result is a cartridge that becomes slightly longer than it came from the factory (or from the reloading bench). The additional length is visible to the naked eye. More significantly, if the crimp jump causes the front of the bullet to protrude out of the cylinder, the bullet will collide with the forcing cone of the barrel, and the cylinder is prevented from rotating to a firing position. To put it succinctly, the gun locks up and cannot be fired.
A couple of months ago, while test firing some factory ammunition from a reputable manufacturer, I experienced crimp jump in the Alaskan. It took me several seconds to realize what had happened, and several seconds more to correct the problem (a two-handed operation that involved a bit of finesse). After discussing the incident with Ruger, the manufacturer of the round that jumped crimp, and other ammunition makers, I concluded that no single entity was to blame. The simple truth is that when such a powerful cartridge is shot from such a small gun, crimp jump is a very real possibility.
This photo shows the bullets protruding slightly through the cylinder, due to crimp creep. These rounds can not clear the forcing cone, and will cause the gun to lock up when attempting to cycle the action.
When a backup gun (like the Alaskan) locks up, the seriousness of the situation cannot be overstated. If you don’t believe this, consider where and when this gun is intended to be used: when you’re in the wild and have just been surprised by a large, aggressive bear. More often than not, you’ll be within 50 feet of the animal, and if your gun locks up — even for only a moment — you’ve got a major problem on your hands. Even if you know how to free the gun’s action, you still have to reload it to get it to fire. I doubt many shooters are quick enough to do this before the bear would be upon them.
The purpose of this test was to evaluate several .454 cartridges for their susceptibility to crimp creep. The goal was to provide a test cartridge with multiple opportunities to jump crimp by exposing that cartridge to the recoil of many (more than a single cylinder-full) firings of other cartridges. I hoped that this acid test would reveal which cartridges were more resistant to crimp jump.
- From a pool of ammunition, designate a small number of test cartridges. Identify these cartridges by marking the cases with a felt pen or something similar.
- For each test cartridge, measure the initial Cartridge Over-All Length (COAL).
- Load the SRH cylinder with the test cartridge and five other cartridges.
- Close the cylinder so that the test cartridge would fire sixth if all six rounds were fired.
- Fire a single round.
- Open the cylinder and remove the test cartridge.
- Measure and record the test cartridge’s COAL, and reinsert the test cartridge.
- Repeat steps 4 through 7. Each time the cylinder is closed, the test cartridge should be positioned as the final of the unfired cartridges.
- When the test cartridge COAL approaches 1.800, attempt to chamber the test cartridge in single-action mode in between each firing. This is to determine exact point at which the test cartridge can no longer chamber.
- Terminate the test when the test cartridge no longer can chamber, or at the completion of 25 test firings.
Equipment Used In the Testing
An Oehler Research chronograph was used to measure velocity of the ammunition. Oehler has a reputation for being the top of the line, and after working with it for several hours of testing, I can understand why. Their product is easy to install and use, and delivers accurate, reliable results.
A Ransom Rest was used for measuring results firing from a fixed bench rest. Ransom manufactures rests for handguns and long guns, and their products are beautifully made, reliable and very helpful.
A Starrett digital calipers with accuracy to .0005" was used in the cartridge measurements.
Finally, a pair of Past Shooting Gloves saved the author’s hands from a lot of abuse!
Summary and Conclusions
First of all, it needs to be noted that all cartridges tested successfully endured at least five firings. This suggests that any of these selections are a safe choice for a cylinderful of firings. (It’s also noteworthy that if you can’t get the job done in six shots, you’re in big trouble anyway, as you may not get the time to reload.)
Second, when selecting ammunition, there is probably more to consider than the sheer number of firings a cartridge can endure. Velocity, bullet style (do you want an expander or a penetrator?) and predictability all matter, too. Also, the cases of some brands of ammo can be tough to eject once fired. You’ll want to take all these factors into account when making your selection.
It was particularly revealing to see the difference between hand-held and rest-held shooting. Bullet creep was substantially reduced in rest-held shooting. While it’s unlikely that you’ll have the benefit of a rest (and bench) when you need to use this gun for self-defense, there still is a lesson to be learned here: that how the shooter holds and controls the gun during firing can have a (minor) impact on crimp jump.
Finally, this test has made it obvious that firing .454 ammunition is quite, shall we say, stressful to other cartridges in the gun. I would strongly recommend that, if you use your .454 as a backup gun, that you rotate your ammunition. Better yet, when you’ve shot a couple of rounds, simply go ahead and fire off the other rounds in the cylinder. Starting with fresh ammunition every time is probably the best insurance against crimp jump and the potential disaster that could result from it.
If you have any questions or comments, or would like to submit another brand of ammunition for testing, please feel free to contact the author at the author’s email. I welcome your input.