CorBon Jacketed Hollow Point Loads

For the .45 ACP

by Mike Cumpston

edited by John Dunn

Click on any thumbnail for a larger photo.


230 JHP Average Velocity

230 JHP Energy

230 JHP Extreme Spread

230 JHP Standard Deviation

975

486

44 feet per second

13

Recently, while I was plotting out an overview of the CorBon line of pistol ammunition with the editor of a famous print magazine, the editor mentioned that it would be beneficial to be as objective as possible. The gun magazines receive a fair amount of criticism for seemingly foisting off rave reviews of everything that comes through the door. I did the best I could and informed the readership that my deep-seated bias in favor of the stuff came about over a period of years and reached full strength long before Dakota Cartridge began sending me samples to test. A number of the loads in various calibers have become my first tier choice as serious carry rounds.

The CorBon line has grown quite extensive with a wide selection of loads geared toward defensive use and a large and growing variety of offerings specifically designed for hunting and other sporting applications. There are several distinctive elements that appear consistently across their entire range of products. Predictably, the cartridges provide greater velocity and energy than similar rounds from competitors in the industry. Likewise they exhibit higher velocity/energy than advertised while remaining within the pressure envelope established by the Sporting Arms and Ammunition Manufacturers Institute (SAAMI) for +P ammunition. These trends are consistently demonstrated over my personal chronograph and it is also significant that the rounds show a high degree of consistency in reference to low extreme spreads and statistical measures of variance.

Deja Vu All Over Again

Against this background, the arrival of a care package of the 230 Grain JHP variant was something of a case of deja vu all over again. One of my immediate concerns was neither scientific nor in perfect accord with the purposes of Dakota Cartridge. To wit: How do I do a thorough evaluation of this round and manage to end up with a couple of magazines of the stuff left over for my personal use? I was that confident of its goodness. The round consists of a markedly truncated jacketed hollow point loaded into a heavily cannulured case which should eliminate any possibility of deep-seating by the most vociferous of autopistol cycling sequences. A tapered "profile" crimp is visually evident and the overall length is only marginally shorter than Remington hard ball. The hollow point is extremely wide and deep bringing to mind the old Speer 200 grain Flying Shot Glass or the Speer Gold Dots designed for subsonic velocities. The jacket, consistent with the current generation of jacketed hollow points, completely covers the lead core and is serrated to augment expansion. By contrast an older version of the 185 grain CorBon JHP presents a slightly shorter Cartridge Overall Length, the bullet is less truncated and more tapered and the hollow point is much smaller than the load under observation. The arrival of a comprehensive sampling of the entire CorBon .45 ACP line reveals that all of the current JHP loads match the 230 grain weight in bullet profile and overall length. The only clue that the cartridges have different bullet weights is the location of the cannulure on the case.

Sub Sonics

Until relatively recent times, available jacketed hollow point bullets did not expand worth a flip until they reached velocities well in excess of the speed of sound. Across the board there has been observed a tendency for JHPs to fill up with barrier material such as heavy clothing and fail to expand. This factor seems to be more pronounced at lower velocities and far less significant at magnum velocities. Since the 230-grain .45 ACP load falls into the former category, I took this into account in selecting my bullet collection medium. I have an old thick canvas bag with the zipper out of it and a double thickness of blister-packed pork ribs fits neatly inside. I placed this in front of a Coleman cooler loaded with gallon water jugs. In this wise, I was able to collect several bullets and observe the signature of several more on the rib pack after the bullet had first passed through the equivalent of a tent cloth duster. In every case the bullet expansion in the pork rib back was immediate and gratifying. Those recovered bullets that did not fragment, expanded to .75" and all recovered bullets retained the major portion of their jackets. There was no observable difference in bullets fired from ranges varying from 15 feet to 25 yards.

The CorBon line now provides enough of a selection for the customer to express his own ballistic preferences in regard to bullet weight, velocity and relative frangibility. I checked out the 165, 185 and 200 grain offerings with the above canvas bag, meat and water but substituting a 3-4" thick fat-marbled brisket for the ribs. Recovered bullets demonstrated profound fragmentation of the two lighter weight bullets while the 200 grain expanded to 70+ caliber and more closely resembled the profile of the 230 grain bullets.

Velocity!

The 230-grain load is rated at 950 real world, 1911-A1 feet per second and, typical of CorBon products, exceeds the advertised performance. With the temperature in the high 60s my chronograph read off a ten round average of 975 fps with energy factoring in at 486 foot pounds. Extreme spread was 44 feet per second with the slowest round reading 954 and the highest 998. Standard deviation was a match load-cheerful 13 feet per second. This exceeds the nominal velocity of generic ball in a very +P manner. My 9.5" Ruger Convertible revolver recorded a modest increase in velocity with velocity at 992 fps and energy registering 502 foot pounds. I had fired only five rounds and extreme spread was 35 fps. (Five round averages are only a reference check, so I didnít include Standard Deviation.)

I spot checked five rounds each of the 165 , 185, and 200 grain loads as well as a five round sampling of PowRball finding that they exceeded the advertised velocities in the usual manner and gained substantial velocity fired in my Ruger Blackhawk with the custom 9.5" Barrel.

165 Grain CorBon JHP Velocity/Energy/Extreme Spread

1911: 1261 583 40

Ruger: 1390 708 62

185 Grain CorBon Velocity/Energy/Extreme Spread

1911: 1162 555 14

Ruger: 1229 621 53

200 Grain CorBon Velocity/Energy/Extreme Spread

1911: 1085 523 33

Ruger: 1150 587 45

PowRball 165 Velocity Energy/Extreme/Spread

1911: 1265 586 45

Ruger: 1343 660 55

Hitting Things

The CorBon 230s arrived as I was in the middle of checking out and generally enjoying a profoundly accurate Springfield milspec, magically transmogrified by Alex Hamilton of Ten Ring Precision. I had recorded groups with generic ball of well under 2" for five shots at 25 yards and had piled up a count of one inch and under groups with several target loads. Forget "combat accurate": this pistol is as accurate as they come. I moved to the 25 yard bench and fired two consecutive groups with the 230 CorBon that measured slightly over 1.5" and 1.6" respectively. A subsequent ten-round string landed eight inside of 2" with a couple of shooter-caused fliers expanding the cluster to 2 ĺ". Any load I can shoot this well from a casually assembled bench rest is rabbit and squirrel accurate if the shooter is up to the task.

My groups with the three sub-230 grain JHP loads ranged from 2.4- 2.7" with the Springfield 1911. The largest group from the Ruger was 1.9" with the 200 grain bullet load and the .90" five shot cluster from the 165 grain load is the smallest fired from that revolver to date. I observed that all of the JHP loads were striking at very nearly the same point of impact at 25 yards--a boon to the fixed sighted utility pistol. In my two 1911ís the PowRball load has been providing "combat accuracy" with groups in the 2.7-3.5" range and slightly better from the Ruger. This round is designed to provide ball-equivalent functioning in those semi-autos that are less than totally reliable with JHPs.

Truth in Advertising

CorBon has a long-standing and effective advertising program now extending to the internet at http://www.corbon.com. . In so far as I am equipped to test their claims, my results are fully in accord with advertised performance. This makes me believe that other declarations about performance against barriers and tactical effectiveness are valid also. The Company subscribes whole-heartedly to the Marshall Sanow School of Stopping Power. This is not surprising since the CorBon rounds occupy the upper reaches of calculated, observed and otherwise claimed effectiveness "on the street."

At the beginning of this experiment the milspec had not yet been "certified" for any JHP load but had demonstrated excellent reliability with just under 1,000 rounds of factory ball and my hand loaded target rounds. In general, fully throated 1911s of current manufacture function JHPs with the same degree of reliability as ball ammunition and the CorBon fit this mold exactly. Dry cycling was smooth and uneventful and live fire was likewise uneventful. I had arrived at the range with a gun full of 230 grain generic ball. At the end of the day, my carry gun was filled with the CorBon 230.

Hit Counter since the website crashed AUG 2003, original publish date was 17 Nov 2002

 

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