CENTIMETER: The Gun Click here to read about the Centimeter Cartridge
American Handgunner, July/August 1987
Centimeter is the name of the new cartridge designed for IPSC competition. Chamber it in a thoroughly customized Colt from Pistol Dynamics and you have the latest technological edge.
By Cameron Hopkins
Shaka, king of the Zulu, revolutionized African warfare when he shortened the ineffectual throwing spear into the deadly assegai, a bobbed-off stabbing spear. Shaka's impi battalions conquered most of southern Africa on the point of the assegai.
That was the last time an African took an existing weapon and shortened it, thereby making it more efficient. A century later, another African has taken an existing weapon, shortened it and rendered it more effective.
Working with a 10mm Norma cartridge shortened by a tenth of an inch, South African expatriate Paul Liebenberg developed a customized Colt Model O for the Centimeter cartridge. Like Shaka's triumphant warriors, Paul is excited about his 20th century assegai.
And also like Shaka, Paul is a prince who pretends to the throne. Paul hopes to wash his spear in the blood of the reigning monarch of IPSC shooting, the .38 Super. The Centimeter custom Colt is designed to surpass and dethrone the super Super.
So we approach this report on the refined Centimeter pistol with that in minda competition pistol in a dynastic clash with the ruling family. Can the Centimeter usurp the Super's kingdom?
Pistol Dynamics is Paul's gunsmithing firm, and Pistol Dynamics supplied identical custom pistols, one in Centimeter and one in .38 Super. My report and the majority of my shooting tests are concerned with the Centimeter.
Did the Centimeter pistol mop up the Super? Did it squash its rival as Shaka crushed all who opposed him?
Yes, no, perhaps, definitely maybe. I find the Centimeter pistol superior to the Super in all aspects except one: magazine capacity. Modified Super mags hold 10 rounds while I can only fit nine in the Wilson .45 mags I use with Centimeter. Pistol Dynamics claims that ten-rounders are possible, but I have not seen one.
In all other respects - accuracy, recoil, handling - the Centimeter is better than the Super, according to my tests. The Pistol Dynamics conversion of the Colt to Centimeter is amazingly accurate to the tune of sub-two-inch groups at 50 yards. The Centimeter is one of those wonderful, inherently accurate rounds. The handling of the pistol, the feeling and sensation as the gun cycles, is smoother and gentler than a Super. The reloading is not cheek-to-cheek with the Danger Zone like the balls-to-the-wall Super. And most importantly for the IPSC shooter, the muzzle jump and felt recoil are softer and less abrupt than the Super.
My overall impression of the workmanship is that Paul's custom Centimeter is a masterful execution of exquisite pistolsmithing. The metalwork is the finest I have ever had the pleasure of examining.
The first step is converting a 1911 pistol to Centimeter is to open the breech face of either a 9mm or .38 Super slide to accommodate the 10mm Auto case head. The extractor is modified to fit the Centimeter, and the selector is similarly remodeled.
From there Paul fits a Centimeter barrel from Bar-Sto. Paul enthusiastically credits Bar-Sto's lrv Stone as being crucial to the development of the Centimeter pistol, lrv tooled-up to make the Centimeter barrels when the entire Centimeter project was in its infancy and still purely experimental.
The bottom lugs and swinging link are whacked off the barrel and replaced with a patented Pachmayr "wide link” which is an innovation from the Pachmayr Signature pistol. The wide link is an ingenious improvement. Paul explains:
"It's like putting wide tires on your car. You either run on biscuits or you run on big-fat-wide tires. So we take a wide link to stabilize the barrel. It's the logical thing to do because the wide link is so broad. It's as wide as the actual legs on the barrel. In and out of battery, the barrel stabilizes on the slide stop pin."
In conjunction with the wide link, Paul replaces the slide stop pin with one that is .005" over-size. More bearing surface. The wide-link/over-size pin together make for a system that, essentially, is self-accurizing. As natural wear and tear grind away a thousandth here and a thousandth there, the camming action of the wide link continues to operate and compensate for the loss of tolerances.
Paul maintains that an accurized pistol with a conventional link needs a tune-up after 18,000 rounds. With proper cleaning and lubrication, Paul said the wide-link system is good indefinitely.
The Pistol Dynamics gun has a long Pachmayr plastic trigger tuned to a brisk two- and-a-half pounds. This is a fine trigger job with no appreciable take-up and no hint of sponginess.
The beavertail grip safety is handmade, sculpted from a block of steel. Paul's handmade grips safeties have been his trademark ever since he began his career in South Africa. The style of the beavertail allows the hand to grip the pistol slightly higher which elevates the hand closer to the axis of the bore. This in turn helps control muzzle flip.
And the metalwork of the beavertail - gorgeous! - is exemplary of the rest of the artistry-in-steel. The magazine release button is handmade from a chunk of steel, checkered and blended into the Pachmayr stocks.
The pistol is fitted with Swenson ambi thumb safeties that Paul re-contoured to provide a larger, more positive surface for flicking off the safety. In addition, a Pachmayr thumb guard rides shotgun on top of the port thumb lever to prevent the shooter's thumb from rubbing the slide. With a "high thumb" grip, you can stifle the slide's cycling without the thumb guard.
The trigger guard is squared and checkered at 30 lpi. The rear of the slide is checkered at 40 lpi. While both of these examples of Paul's checkering are flawless, I am more impressed with the front strap checkering.
I closely inspected the front strap 20 lpi checkering with an 8 x magnifying glass and I could not detect any imperfections. In fact, I looked hard for just one dulled diamond, for any hint of an over-run, for the slightest blemish. None. I have looked at checkering from some of the most famous names in the business, and all that checkering pales in comparison to this.
The flat mainspring housing is also checkered at 20 lpi. Like the front strap, this checkering provides a sharp, slip-free surface for a firm purchase on the weapon.
Superlatives are in order for all the metal work. The swaged magazine well and funnel defy the slightest hint of tooling marks, evidence of welding or signs of an add-on. The magazine chute is the most tasteful execution of this popular option for facilitating rapid magazine reloading that I have ever seen.
Bo-Mar adjustable sights are not merely dovetailed into a hogged-out slide. The Bo-Mar unit is manicured. Rather than just lopping off the back of the slide, Paul makes four cuts instead of one and the result is a buried Bo-Mar with more finesse than is usually encountered.
Needless to say, all internal bearing surfaces are polished like a shining marble floor.
The ejection of spent cases is tediously refined until all empties sail out at a 35° angle. In test firing, I fired several magazines, just blindly pointing downrange, and watched the hulls fly. I couldn't tell the angle - I usually don't shoot with a protractor in my handbut all the empties zinged in a consistent arc and landed in a tidy pile. Paul explained this is accomplished with a carefully modified ejection port and precise honing of the extractor and ejector.
Such attention to minutiae is indicative of the many subtle fine points of the Centimeter pistol.
Another fascinating innovation from Pistol Dynamics is the compensator. Perhaps I should say "a" compensator instead of "the" compensator because Paul offers three different comps. Paul has done extensive research into comps, with the help of ballistician Whit Collins, and has discovered that compensators affect accuracy. Also, he's uncovered three designs that differ in their accuracy potential and recoil reduction.
The three compensators allow a competitive shooter to select a balance between recoil reduction and accuracy according to his needs. The most accurate comp is the least effective at muzzle jump reduction, and the most effective recoil reducer is the least accurate. However, the differences are subtle. Were talking less than an inch difference in accuracy at 50 yards and less than two inches of difference in the printing of double-taps at 15 yards.
For IPSC shooters, the favored choice is the comp most effective at recoil reduction. For Bianchi Cup shooters, the most accurate comp is the best bet. Comp No, 2, in the middle, is the best compromise for the shooter using the same gun for both styles of competition.
The Centimeter pistol I tested has the recoil-effective compensator. It is an expansion chamber design with the "scoop nozzle" as pioneered by Jim Boland and his Double D comp. Paul improved on the Double D design by sculpting the sides and changing the free-bore dimensions.
The accuracy is beyond reproach for IPSC applications. The gun shoots an inch-and-a- half at 25 yards from a hand-held rest. By way of comparison, the most accurate comp shoots a half to three-quarters of an inch at 25 yards. I did not test the other comps, but I inspected test targets provided by Pistol Dynamics.
The compensator is threaded onto the Bar-Sto barrel and utilizes a solid bushing for the lock-up. Paul claims the cone-style lock-ups are inherently less accurate and subject to faster loss of tolerances through wear than a conventional bushing lock-up. A recoil spring guide rod is fitted beneath the barrel and comp.
Shooting the Centimeter pistol is a pleasure. I shot several different loads, but the runaway favorite is the 165 grain lead flat point. The sensation of the pistol firingthe recoil, the slide movement, the muzzle rise, the over-all cyclingis more like a .45 than a .38 Super. The feeling is one of a gradual shove rather than a sharp jab. I have shot a number of custom Supers and I have always perceived them as being "sharp." I shot and compared a Pistol Dynamics .38 Super outfitted identically to the Centimeter pistol. I did not shoot a Pistol Dynamics .45.
However, other loads did not compare favorably to the .38 Super. A 200-grain flat point jumps just a tad less than a .45. A very slight difference the Super is certainly superior in recoil reduction to the 200 grain Centimeter.
I also tried some 170 and 175 grain Centimeters, and while they are improvements over the .45, they are not less jumpy than the Super.
Conclusionthe 165 grain Centimeter is the clear choice for an IPSC competitor. I found it softer than a Super.
All of the loads power factored (bullet weight x velocity over 1,000) between 168 and 175.
I found double-taps could be consistently kept in the elongated A-zone of the IPSC target out to 15-18 yards. Out at 20 yards, frequently the second shot flew into the neck or shoulder areas. Personally, I do not double-tap (one sight picture, two fast slaps on the trigger) beyond 15 yards in a match because that is just too dicey. The Centimeter is more than capable of A-zone hammers out to 15 yards.
The Pistol Dynamic's gun tested and pictured here costs $1,500 with all these refinements, excluding the price of the base gun. Add in the retail price of a Colt Series 80 Government Model, and you're looking at two grand.
The driving force at Pistol Dynamics is master "re-constructor" Paul Liebenberg. Paul was formerly the manager of Pachmayr's custom pistol division before Pachmayr shut down their in-house custom shop. Now under outside contract from Pachmayr Gun Works, Paul and his associates at Pistol Dynamics build all the Pachmayr Combat Special and Pachmayr Presentation models.
Pistol Dynamics also operates independently by offering a wide variety of custom pistolsmithing services, including the Centimeter conversion.
A simple re-barreling to Centimeter on your gun costs $250 and that includes a Bar-Sto barrel, breech face work, fitting and accurizing.
A top-end conversion (you supply a frame) costs $750 which includes a new Colt slide, Bar-Sto Centimeter barrel, compensator system, Bo-Mar sights, 35° ejection port work and all fitting and accurizing.
For more information on Pistol Dynamics complete services, write Pistol Dynamics, Dept. AH, 4442 York Blvd., Unit 7, Los Angeles, CA,90041. Paul's assegai is the Centimeter pistol and whether or not he vanquishes the Super, like Shaka massacred his rivals, remain to be seen.