Corbon .45 Auto Rim 160-gr. DPX Report...

[Stephen A. Camp]

Hello. Today I was able to try this new addition to Corbon's DPX line of handgun ammunition. It utilizes a Barnes X-bullet, which is constructed from a copper alloy and contains no lead. DPX stands for Deep Pentrating Xbullet and these have been popular in rifle calibers for years. Unlike the rifle bullets, the Barnes X bullets used in the Corbon DPX ammunition expand via six equidistant petals rather than four.

The auto rim cartridge can be used in .45 ACP revolvers without the use of those pesky moon clips.


The three cartridges in the half-moon clip are .45 ACP. These can be a real pain to load with live ammunition and worse when removing fired cases. Several types of tools aid in the removal process. The AR ammo "operates" just like any other rimmed revolver round.


This is a standard pressure load that has a listed velocity of 1050 ft/sec. It appears to be the revolver-equivalent of the Corbon's 45 ACP "Compact Gun Load," which uses the same bullet and has the same listed velocity.

This ammunition was fired from the only .45 ACP revolver I own, a Smith & Wesson Model 625 w/5" bbl.


This revolver is not compact and not ideally suited for concealed carry, but it's what I had. I hope that the results can still be of use to folks having revolvers with shorter barrels.

This ammo proved accurate at 15 and 25 yards. Groups were fired using single-action, slow-fire, and from a seated position with my wrists braced. To make a long story short, this ammunition groups quite well from the test gun.


Not sighted in exactly right, we can still see that the load is capable of tight groups. These sort of groups are not likely under the conditions for which this ammunition was envisioned, but it's still nice to know that the ammunition is capable of better accuracy than we probably are under the stress of a life-or-death deadly force scenario. At 15 yards using the same POA, the 160-gr. DPX load hits approximately 2 1/4" lower than with standard velocity 230-gr. ball.

Based on 10 shots fired 10' from the chronograph screen, this ammunition yielded the following:

Average Velocity: 1108 ft/sec

Extreme Spread: 37

Std. Deviation: 12

Informal expansion testing was done in water and in super-saturated newsprint, which was soaked for 24 hours and drained 30 minutes before shooting.


From left to right: Corbon 160-gr. DPX fired into water. Winchester 230-gr. Ranger JHP fired into the soaked newsprint and a DPX fired into the same thing. Expansion was reliable and consistent. In the wetpack, both the Winchester and the DPX bullets penetrated approximately the same depths, a bit over 6". The Winchester 230-gr. Lawman JHP is considered an extremely "good" defense bullet and usually penetrates around 14" in 10% ballistic gelatin, which is a bit over the FBI suggested minimum of 12". Corbon's DPX is designed to penetrate at least 12" in 10% ballistic gelatin.

Felt recoil was less than with standard velocity ball to me and checking out the numbers based on both rounds' average velocities from this revolver, the DPX recoils with about 7% less "kick". Fired cases could literally be shaken from the cylinder so folks using smaller .45 ACP revolvers shouldn't have to be concerned with ammunition that might possibly put undue wear and stress on their handguns.

I am advised that the powder used is flash-retardant and of optimum burn rate for use with short barrels.

In short, I am very favorably impressed with this Corbon DPX load.

If interested, a more detailed report is here:

http://www.hipowersandhandguns.com/C...mmo%20Test.htm

For those interested in this ammunition or who have more questions, here is the link to Corbon's site:

www.corbon.com

Best.

[Stephen A. Camp]

Hello. As mentioned in the original report, I normally use Auto Rim cases as I handload for the .45 Auto Rim and use the .45 ACP with moonclips when wanting something that expands or acts differently than the deep-penetration 250-gr. CSWC I normally use.

Checking around, I found that HKS, a long-time maker of revolver speedloaders, offers the 25-M for the Auto Rim. The only revolver on their packaging that they show it for use with is the S&W Model 25-2.

HKS is the brand of speedloader that I use for pocket carry with the .38 Special snub that accompanies me everywhere 24/7 and a brand/type that I've had exactly zero problems with. I am sure that it's not the fastest speedloader, but it is secure, and if using .45 Auto Rim, I suspect it is the only choice.


Here are two of the HKS Model 25-M speedloaders for the .45 Auto Rim. One is loaded with six of my CSWC handloads while the other is loaded with six Corbon 160-gr. DPX expanding bullet loads. The speedloader/.45 Auto Rim combination is a short one, but this is only normal considering that the Auto Rim revolver cartridge sprang from the .45 ACP. The Corbon round uses Starline cases while my handloads are with Remingtons. Both worked fine.

These speedloaders hold the Auto Rim cartridges in the same manner that they hold conventional revolver rounds such as the .38/.357, .44 Special, .44 Magnum, et al, and twisting the knurled aluminum knob releases the cartridges to fall into the cylinder by gravity.

When I initially tried a reload, it seemed like the speedloader was hanging on something. In other words, the cartridges were not going into the cylinder as deeply as I'd grown acustomed to with typical revolver cartridges.
What was the problem? The speedloader had no problems clearing the Pachmayr grips that came on the revolver.


Actually, there was no problem; 45 AR is simply a short LOA cartridge and you can see part of the shaft of the speedloader bumping up against the revolver's spring-loaded center pin. I repeated reloading ten times with both the DPX factory loads and the handloads. I had no problems or failures to reload the revolver efficiently, but Mr. Miculek has nothing to fear from me!


Folks using .45 ACP revolvers can use either moonclips with ACP ammo or speedloaders with AR ammunition rather than carrying the latter loose in a pocket.

I ordered mine from Brownells, but these can probably be found elsewhere for those interested. At Brownells, they cost $9.95 each and are listed by Part Number #392-100-025.

Best.

[rnovi]

Stephan, Thank you very much for doing this report. I don't see myself rushing out to buy the DPX's, but I am grateful to see someone making autorim defense loads.

[rhinospeed84]

Thanks for taking the time to write this post, I found it very informative