Bren Ten the 10 mm powerhouse.
In fact, Jeff Cooper is so impressed with this auto/cartridge combo that he has hung up his Colt 1911 and uses the Bren Ten as his personal sidearm. He also uses the Bren in his official duties as head of the Gunsite Raven Corporation. The logo of Gunsite, a stylized Raven, appears on each Bren Ten.
It is not easy to get a revolutionary new pistol and cartridge in production and the Bren Ten is no exception. Prototypes were shown at least 4 years ago, however, it is just now, May of 1984, that Guns & Ammo received a pair of guns off the regular production run for testing.
For those who are interested, the name "Bren" is tied in with the famous British light machine gun of WWII fame. This gun was developed from a Czech design built at the Brno factory and finalized at the British Enfield arsenal. The two names, Brno and Enfield, were combined to form the acronym Bren.
Brno is still a world leader in firearms design and, in postwar years, produced an advanced double/single-actioned autoloading pistol, the CZ 75 in 9mm Parabellum. Jeff Cooper was impressed with the design of this arm, although the minor 9mm caliber is obviously not his cup of tea. Dornaus & Dixon improved the basic Czech design and beefed it up to handle the hot new 10mm Auto round, as well as the optional .45 ACP cartridge. Col. Cooper suggested that the famous "Bren" accolade be applied to this new pistol with the additional "Ten" to indicate the new caliber.
Although not financially involved with Dornaus & Dixon, Jeff did agree to act as a consultant as far as design features were concerned. His suggestion that the safety be moved lower and to the rear was faithfully carried out even though it meant that major revisions would have to be made to the lockwork. And so it went, until Jeff Cooper was satisfied that the gun was ready to go into production.
Our two pistols consisted of a Standard Model, which features a blued 4140 chrome-moly steel slide mated to a stainless satin-finished frame, and a Military/Police Model of the same configuration except that the stainless frame is finished with a black oxide. All other specifications are identical. Incidentally, this combination of conventional steel and stainless steel was a carefully thought out design objective. It is well known that stainless steel rubbing on stainless steel can cause galling.
It is also well known that the American shooting public likes stainless for its corrosion-resistant features. The Bren Ten combines these two metals where it is felt it will do the most good. The corrosion resistant stainless is used on the frame, where is contacts sweaty hands, and the carbon steel slide rides effortlessly and without galling on this frame. This was not an arbitrary decision. The first prototype had both a stainless slide and frame, however, galling developed after about 1,000 to 1,500 rounds when the protect 10mm ammo was fired in this combination. Dornaus & dixon then tried to use dissimilar stainless steels in the frame and slide and have them heat treated to different hardnesses. Again, all was well until about 1,000 rounds churned up the barrel and galling again reared its ugly head. For these reasons the Bren Ten now boasts the combination carbon steel slide and stainless frame.
The pistols come with fully adjustable rear sights and with a front sight that is relatively easy to replace should it be damaged, or should you wish to replace it with a sight of a different height. Originally the bushing alone retained the sight in its slot, however, exhaustive tests revealed that the bushing could loosen under sustained recoil leaving the front sight somewhat loose . . . hardly conductive to pin-point accuracy! The sight barrel bushing was modified to include a roll pin which locked both the front sight and the barrel bushing into place so that they could not possibly jar loose, no matter how many rounds were fired. To remove the bushing and replace the front sight it is necessary to use a 1/16-inch drift punch to drive out the roll pin once the slide is field stripped. The base of the magazine can then be used as a wrench.
The rear sight requires an Allen wrench, which is furnished, to make windage or elevation adjustments. The rear sight had two white dots that line up with the single white dot on the front sight for a rapid, eye-catching sight alignment.
The pistol, unlike most double-action autos, can be carried "cocked and locked" a la the Colt 1911. Thus your first shot from the leather will have the same pull and finger position as do all subsequent shots. With the conventional DA pistol, your first shot, unless you take the time to manually pull the hammer to full cock, invariably has a long, heavy trigger pull that is totally different from the single-action trigger release. In addition, your finger must be repositioned for a proper single-action release. This has always been the bugaboo with double-action autos. For many years Jeff Cooper has said that: "A double-action auto is a solution for a problem that does not exist."
The Bren Ten solve. Jeff's objections to a DA auto--since it can be carried cocked and locked--while at the same time it does cater to those less professionally trained than Jeff who like the double-action first-shot capaility. There are also police departments who are vitally concerned with the image projected by an officer carrying a loaded, cocked autoloading pistol. The general public, more in tune with revolers than autos, get downright nervous when they see an officer carrying a pistol in a condition that they, out of lack of knowledge, deem dangerous.
So, without question, the double-action capability of the Bren Ten is a definite plus factor. It obviously also cut into the argument that a revolver is more reliable than the auto pistol. If you have a misfire with the Bren Ten another tug on the DA trigger will strike the printer an additional blow and, unless you have dud ammo, this is usually enough to fire the round.
The Bren Ten is loaded with safeties although, thankfully (and no doubt due to Jeff Cooper's urgings), it does not have a magazine disconnect. It can be carried loaded with the hammer down ready for a quick DA shot, loaded with hammer down and thumb safety engaged for a reasonably quick DA shot, cocked and locked for single-action firing of the first shot, or a combination of all of the above the conjunction with a firing pin lock.
The firing pin lock is located just below, and forward of, the rear sight. It is a circular insert in the serrations that help you get a firm grip to pull back the slide. When pushed in, left to right, it positively locks the firing pin so that the hammer blow cannot be transmitted to the primer. It is released, naturally, by pushing the now protruding boss back to the left. The release requires either changing the grip of the strong hand or using two hands. I must admit to lingering suspicions that this is one feature that Col. Cooper did not request.
However, just the like the legend on the right side of the frame that states: "Free manual available from: Dornaus & Dixon Ent., Inc. Hungtington Beach, CA" it seems to be one of the things we now have to live with. This is 1984 and Big Brother is going to protect you whether you want to be protected or not. On the positive side, this feature will probably also rate high with law enforcement agencies. Many officers are killed or wounded with their own guns and an unobtrusive safety like this might well be overlooked by a criminal. This could give the officer time to recover a snatched pistol and give the "perpetrator" remedial instruction in pistol craft.
One feature mandated by Jeff Cooper was a lanyard ring. Seldom seen on contemporary arms, this is an entirely practical item. For one thing it is damn hard to take a pistol away from somebody who is physically connected to the piece. In addition, a properly adjusted lanyard can be a great and in steadying a pistol in the field. A small item, but indicative of the thought put into this pistol's design.
Another little gizmo that could well be overlooked, as its utility is not readily apparent, is a screw located on the lower part of the right-hand grip. When the slot in the screw head is tilted toward the pistol's muzzle, the magazine will drop free from the frame when the magazine release is pushed. Turn the screw slot to the horizontal, a distinct click will be felt, and the magazine will not fall free when the release is pushed. Instead it will drop just far enough to be grasped by the hand and then can be easily pulled from the magazine well which is, of course, funneled. This allows the shooter an option of dropping the magazine during a combat course where he is at liberty to later retrieve the magazine, or opting to remove the magazine manually if he is just practicing.
Say you don't have a screwdriver to turn this magazine control slot? Don't panic, Jeff and the folks at Dornaus & Dixon have thought of that. The recoil spring guide has a dual (triple?) function, as it obviously aligns the recoil spring, acts as a recoil buffer, and it also has a screwdriver tip to complete the field disassembly of the Bren Ten or to turn the magazine adjustment screw. A very neat bit to functional designing.
Incidentally, takedown of the Bren is extremely easy. Based on the tried-and-true Browning short recoil system, it is quite similar to the Browning Hi-Power. First remove the magazine and then rack back the slide to make absolutely sure that the chamber is clear. It is also a good idea to engage the firing pin lock and then raise the hammer to the half-cock notch. Once you are certain that the pistol is unloaded, pull the slide to the rear about 3/8 inch while pressing on the slide release pin which extends from the right side of the frame. When this pin snaps into the frame you know you have reached the dismounting notch in the slide. Then grasp the slide stop, while still retaining pressure on the mainspring, and pull it out of the frame to the left. The side can then be easily eased off the frame.
If I were to believe the owner's manual I would, at this point, engage the services of a doctor, a dentist, and a lawyer as well as bundling up in protective clothing and donning both eye and face protection. In short we seem to be facing a crisis situation at this point. We have a spring under tension! Of course if you are not a buffer-fingered dolt you will merely grasp the recoil spring guide, pull it back a smidgen, and remove it as well as the spring and spring/tube bushing lock from the slide. I grieve for Dornaus & Dixon and long for the days when, if somebody were dumb enough to let something under tension fly loose, they would sheepishly look around to see if anybody had observed their stupidity instead of trying to sue the world at large.
At any rate you now have the Bren Ten field stripped for normal cleaning and maintenance. If you are a southpaw you can continue to strip the frame until it is possible to reverse the position of the safety to left hand use. This is a fairly complicated maneuver that is fully covered in the owner's manual.
The 10mm barrel features "power-seal" rifling, from a design by Barret "Boots" Obermayer. It is claimed that this rifling has less effect on bullet deformation, lowers peak pressures, gives better bullet sealing and is highly accurate. Norma states that, using a test barrel so rifled and their factory ammunition, they achieved 10-shot groups of under 1 inch at 100 feet!
Factory ballistics state that the 10mm Auto cartridge launches a 200-grain, truncated cone, full metal jacketed bullet at 1,200 feet per second (fps) at the muzzle. Our own chronograph sessions indicated that this is not type and that the .40 caliber bullet does indeed sizzle out of the 5-inch barrel. The 10mm Auto round has slightly more energy at 200 yards than a .45 ACP--using a 230-grain bullet at 850 fps--has at the muzzle! At 100 yards the contest is not even close; the .45 ACP's velocity has dropped off by almost 100 fps and the energy is just 291 foot pounds. In contrast to the .45 ACP, the 10mm is still buzzing along at 1,025 fps with an energy of 466 foot pounds.
At the time of this writing, complete ballistic tables were not available from Norma. The figures used for the 10mm were determined through the use of a computer program from Pab Software run on an Apple computer.
When the Bren Ten's 10mm cartridge ballistics were run through the Hatcher formula they outpaced the .45 ACP by a narrow margin, but the .40 caliber definitely does come out on top. My own figures were slightly different than those furnished by Dornaus & Dixon, but then the RSP is just that, relative stopping power. The "relative" is the key word here. You are only putting each cartridge in perspective against another. My own calculations placed the 10mm over the .45 ACP by a score of 60 to 67 with the 10mm the Winner. Different methods of calculating bullet nose shape or other formulas could have easily changed the numbers, however, since my formulas for both the .45 ACP and the 10mm Auto were consistent, my relative values maintained a constant. The bottom line is that the .40 caliber 10mm has a definite edge in relative stopping power, foot pounds of energy, velocity and flatness of trajectory over the .45 ACP.
The power edge of the 10mm was amply demonstrated on a simple penetration test using dry telephone books. The .45 with the 185-grain high-speed hollow point loading managed to edge its way through 2-3/4 inches of paper. As usual with hollow points when fired into sand or a paper medium, the hollow point plugged up with the pulp and the bullet acted more like a solid. The 230-grain hard ball only nosed it way through 2-1/4 inches, apparently because it keyholes and ended up resting sideways. The 10mm Auto's 200-grain bullet blasted its way through a full 7 inches of the books!
Tests at Gunsite proved that the 10mm slammed into the ballistic pendulum with more force than the .45 as the pendulum was moved a further distance. Obviously the 10mm qualifies as a major caliber in all respects.
Bren Ten literature indicates that this 10mm pistol has the same felt recoil as a .45 in the same pistol. We did not have a .45 ACP conversion kit for a Bren Ten so our tests involved firing the 10mm Auto and then picking up a standard Colt 1911 and touching off a .45 ACP round. Recoil can be subjective thing with many factors entering into a person's perceived felt recoil; however, several shooters all agreed that the 10mm felt like it had a sharper kick than the old .45 cartridge.
To confirm this, the recoil was calculated through another computer program that had the weight of the pistol, weight of the ejecta which includes bullet weight and powder charge, muzzle velocity and a factor for handgun recoil entered into it. The conclusion? The computer said that a 2-pound, 10-ounce .45 (weighed with seven rounds) and a 2-pound 14-1/2 ounce Bren Ten (weighed with 10 rounds of ammo) had the following energies: .45 ACP, 5 pounds and the Bren Ten, 7.2 pounds of recoil energy. This seemed entirely consistent with your test shooters' feelings which indicated a slightly greater, but not uncontrollable, recoil for the Bren Ten and its hot new 10mm cartridge.
And when we say hot we mean that! Printed on the side of the Norma factory ammo box, which, incidentally, holds 20 rounds, is the following information: "This product is intended for use in firearms warranted by the manufacturer of the firearm to have been proof load tested at pressures in excess of 53,300 psi and having a valid proof mark on the firearm. The ammunition contained herein is factory loaded to develop a mean pressure of 37,000 fps with a maximum pressure of 44,400 psi plus or minus industry tolerances."
Modern handgun cartridge have certainly come a long way since they now operate at rifle-like pressures. I must say that the fired cases look like they have been subjected to high pressure as the primers are really flattened. Ejection of fired brass is noticeably brisk and the empties are tossed some 25 feet from the pistol.
Factory literature states that the Bren Ten should only be fired with Norma factory ammunition. However, it also, curiously, lists sources for reloading components and dies. Since Norma is said to have developed a special powder for this cartridge a call was placed to Outdoor Sports headquarters, importers of Norma ammunition and powders. They confirmed that data would be forthcoming but were unable to quote anything over the phone. When Guns & Ammo does receive definitive information on loading for this new round we will report on it in depth.
In the meantime a factory cartridge was broken down of examination. It proved to be loaded with a .40 caliber 200-grain jacketed bullet backed by 9 grains of a very fine stick powder. Measurements taken from a factory round showed an overall loaded length of 1.25 with a cartridge case length of .989 and a bullet length of .687 inches. The primer pocket takes a standard large pistol primer.
While the current cartridge is loaded with a fully jacketed truncated cone bullet we have been assured that a hollow point bullet, with the same shape, is in the works. For steel popper plates the solid bullet should be just the ticket; however, sportsmen seeking a defense round will probably opt for the hollow point. With ten rounds in the magazine and one up the spout the Bren Ten should be a formidable defense arm. Incidentally, the pistol comes stock with a throated chamber and polished feed ramp so feeding of hollow points should be no problem.
Other stock features are a factory trigger job, enlarged ejection port, beveled magazine well, matted sighting surface and all corners and edges have been rounded for a snag-free fast draw. In short Dornaus & Dixon claim that the Bren Ten, out-of-the-box, is ready for sport or competition without may alteration or add-ons. Their own accessory list is thus quite limited; conversion kits for .45 ACP or .22 LR, spare magazines and an ambidextrous competition safety that must be factory installed.
Range conditions during the field testing of the Bren Ten were atrocious, with gusting winds blowing at least 30 miles an hour along with occasional clouds of windstirred dust. Even so, the pistol performed well with no stoppages or malfunctions even though several hundred rounds were fired. The only problem encountered with either of the guns was when the casting that forms the firing pin safety latch fractured on one gun. One side of this piece fell out which did not affect the functioning or firing of the pistol. This piece was replaced and firing continued on another day with no more problems. Michael Dixon informed us that this was the first time they had ever experienced this and consequently inspection of this part would be more rigorous in the future.
Despite the gusty wind there were no problems blasting rapid fire, full magazine loads into the center of silhouette targets at combat ranges. Recovery time was fast and the pistol has a fine, natural point. The three-dot sight system allowed rapid lineup of the sight picture.
Shots fired into gallon containers of water were not as spectacular as had been anticipated. The full-patch bullet just did not disrupt things the way a hollow point load would at the same velocity. We're certainly looking forward to the introduction of a hollow point loading.
How will the Bren Ten and the new 10mm Auto loading stack up in the field and on combat ranges? With Jeff Cooper's seal o approval it has to be a winner! Harder hitting and flatter shooting than the .45 ACP, the Bren Ten, packed in a pistol that is easily holstered and carried is sure to be the pistol to beat in the future.
For more information contact: Dornaus & Dixon, Dept. GA, 15896 Manufacture Lane, Huntington Beach, CA 92649.
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|Author:||French, Howard E.|
|Publication:||Guns & Ammo|
|Date:||Aug 1, 1984|
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