Technological Oddity: Steyr’s Short-lived GB Pistol
By David Tong
Steyr-Daimler-Puch is an Austrian conglomerate whose main corporate interest is in the production of military vehicles. One of their more famous products is the Gelendewagen, or G-Klasse SUV marketed worldwide by Mercedes-Benz, developed for NATO as a light people mover in difficult terrain. Their arms division is known internationally as Steyr-Mannlicher.
The GB, which stands for Gasse Bremse, German for “gas brake,” is a design that was originally submitted for the Austrian Army pistol trials. This was the first time the firm had a pistol in contention since the turn of the 20th Century Roth-Steyr. However, as everyone knows, it was rejected in favor of Gaston Glock's G17.
Sadly, Steyr’s pistol had a US commercial predecessor known as the Rogak L.E.S. P-18, one of the least reliable modern pistols in existence. Mr. Rogak was a Steyr distributor, and had obtained original patent drawings and a license to build the pistol here in the States in the late 1970's. Due to production errors, lack of adherence to the tolerances of the gas system and poor magazines, it died a deserved death, even though it sported the then largest semi-auto pistol magazine (18 rounds of 9mm Parabellum). Even today, that is the second-largest standard capacity magazine in the caliber.
Thus, when Steyr decided to offer the GB themselves, many, including this author, saw it as horribly unreliable. By manufacturing the pistol to much tighter original specifications, making the magazine tubes of high quality heat treated steel with a “nose-up” and inward-pointing (toward the barrel’s chamber center) cartridge release angle and using a rather unique oval coiled magazine spring, the all steel GB was nearly as reliable as any average service pistol of the era.
The pistol was submitted for the US military trials during the early 1980's, but it failed to win the competition. While the design was accurate and simple (having just 45 parts, compared to the winning Beretta M9, which has over 70), it failed to meet the reliability standard of the “control” handgun, the Model 1911A1. Steyr offered it to the international civilian market, between the years 1984-1988, producing some 15,000-16,000 GB's before production ended. The Author wishes to thank www.stevespages.com for their comprehensive PDF files, including the original Steyr GB manual, which proved a valuable resource when I was researching the information for this review.
The GB is a fascinating artifact. Taking some of its manufacturing cues from the WW II German Mauser and Walther Volkspistole, it features a crinkle-black painted, stamped steel frame, welded along the center spine of the magazine well area and a screwed and pinned plastic trigger guard with an oh-so-‘80's squared and checkered face. The barrel threads into a four spot-welded mounting trunion, which also locates the rear of the conical recoil spring guide. The front interior of the magazine well has a spot welded magazine guide rib, as the sheet metal shell has no means of providing a proper position index.
The slide appears to be of conventional machined-from-forged construction, finished in matte and polished blue. The pistol’s exterior contours are smoothly radiused, which provides a no snag draw under clothing and easy re-holstering.
What is particularly noteworthy is not the method of construction, but the GB’s "gas retarded blowback" method of operation. The Germans experimented with gas-delayed blowback arms toward the end of WWII, most notably in the Volkssturmgewehr 1 (VG-1), to cut down on the amount of material and time needed to produce arms capable of chambering high-pressure service cartridges without locking systems. The pistol’s original design also included selective full-automatic fire, a period design interest that includes others, including the Soviet Stechkin, the Heckler and Koch VP-70 and the Beretta M93R.
The operating system also had a commercial predecessor in the Heckler and Koch P7/PSP of the late 1970's. This used a single gas port ahead of the chamber to fill a gas cylinder below the barrel, with an annular-ringed gas piston attached to the lower front of the slide by a pivot pin. This piston delayed slide opening until gas pressures reached a safe level for ejection of the spent case and cycling the action.
Steyr’s design uses two gas ports (and circumferential gas grooves, which act as a fixed piston) spaced 180 degrees apart, drilled ahead of the gas grooves and it uses a removable gas / barrel bushing or “lock cap,” in Steyr-speak, with interrupted lugs whose interior acts as a gas cylinder under recoil. The instruction manual advises to leave the barrel’s outside diameter and the inside diameter of the gas bushing free of lubricant, to reduce the onset of hardened powder fouling.
The barrel is hard chromed to ease cleaning and the interior dimensions of the bushing are held to close tolerance with the barrels outside diameter and gas grooves. This maximizes the gas braking effect in the expansion chamber thus formed when the slide is in battery, residual pressure subsiding to allow the rearward motion of the slide to re-cock the arm and reload the chamber, with a smallish recoil spring system being sufficient. While this is somewhat simpler than the P7’s recoiling piston, that design has proven itself quite reliable over decades.
Care and Maintenance
To field strip a GB, remove the magazine and clear the chamber. With the slide closed, rotate the right side frame-mounted dismounting latch 90-degrees counterclockwise. This unlocks the barrel bushing, which is rotated counterclockwise 45-degrees and removed by pulling forward and off. Remove the captive recoil spring and guide to the front, then rack the slide to the rear and lift it up and off the short frame rails; ease the slide forward off the barrel. No further stripping is necessary or advisable due to the possibility of losing small and perhaps irreplaceable parts. Reassembly is, as they say, in reverse order.
Cleaning the piece involves removing powder residue from around the barrel and bushing interior. Toothbrush the breech face, magazine (after disassembling it), magazine well / trigger mechanism and clean the bore. Occasionally, I’d use a thin piece of copper wire to clean out the gas ports. Pretty simple and straightforward. Steyr’s smooth machining of the parts makes it easy and not time consumptive.
As can be discerned from the above figures, this is one of the largest service pistols extant. It is larger than a Beretta M9, Government Model 1911, Browning Hi-Power, SiG P-226, Glock 21, or Smith M5906. The only combat pistol I’ve ever owned larger than this was the Heckler and Koch Mark 23, which is nominally the current issue handgun of the Special Forces.
The Steyr GB features traditional double action operation with a trigger-cocking first shot, single-action follow up shots and a spring-loaded left slide mounted decocker only (no manual thumb safety). The decocker has an extension that prevents the hammer from hitting the firing pin. It lacks a firing pin safety block, drop safety being accomplished by the usual inertia-type design with a strong firing pin spring and a rebounding, investment-cast hammer with a sear intercept notch. The mainspring is a clothespin-style coil that powers the hammer fall and the designers were thus able to make the butt of the weapon as small as possible around the large magazine by eliminating the usual hammer strut, hammer strut spring and the use of the thin sheet metal frame. Indeed, the smoothly rounded front and rear strap contours, decent trigger reach, gentle curved lower rear strap and 1911-like grip angle means it is as comfortable as any pistol of its size to use and, to me, more comfortable in butt section than a full-sized Glock.
The low profile front sight is milled integral with the slide atop a non-serrated rib, while the drift adjustable rear sight lacks a setscrew. There is no provision for elevation adjustment, although the three dot system does have luminous paint that will glow briefly when exposed to a strong light source; call it a poor man’s night sight.
The magazine system, as can be seen in the accompanying photo, is unique in my experience for a detachable pistol magazine, in that it features dual-position feed, much as a magazine fed rifle. Most auto pistol mags, even if staggered column in design, taper to single position feed and rounds usually are fed into a feed ramp machined integral with the barrel.
In the case of the GB, however, the bullet noses impact the frame’s feed ramp (part of the frame’s barrel mounting extension) before encountering a lightly beveled chamber entrance at roughly four and eight o’clock during the feed stroke. This design does not feature controlled feed, using instead a small steel extension below the breech face that merely pushes the cartridge forward into the rear of the frame’s trunion/feed ramp. The beveled coil-sprung extractor easily snaps over the case rim after the round seats past the chamfered chamber mouth. Most modern pistols are designed largely to bypass feed ramps and the peculiarities of the feed stroke of the GB does not feel quite as smooth as a result.
However, the magazine’s staggered round feed design does offer one possibly overlooked attribute. It is far easier to load than any other large capacity pistol magazine I have used, as one merely has to push rounds straight down into the magazine tube, rather than having to push backwards and down through the feed lips. This can be quite a chore with a high-capacity magazine, as was the case with the Springfield XDm I recently reviewed for Guns and Shooting Online. One might wish for a giant stripper clip, though . . ..
The trigger is nothing to write home about. The double-action stroke is long, heavy and stacks at over 16 pounds according to the published specs, which must hurt first-round accuracy, while the SA release is roughly 6 pounds with over 1/8” of take-up and a slightly creepy release. The trigger blade is wider than most and has a grooved face. On the plus side, the reset distance is roughly ¼” and both audible and tactile, for pre-staging the trigger for rapid-fire capability.
I was most interested in the fixed hammer-forged, polygon-rifled barrel’s accuracy potential, so I loaded up for another trip to Albany Rifle and Pistol Club’s range for a 25-yard bench session. However, the recent severe windstorm in our area destroyed the 25-yard wood target board, so I fired several fifty-yard groups with both CCI-Blazer aluminum cased 115 grain FMJ ammo and with Remington 147 grain Golden Saber JHP's. I wasn’t expecting the superb results I obtained, as the pistol turned in 3.5” - 4” groups at this distance with both types of ammo. A pleasant surprise, as the combat sights have plenty of light around the front sight, which makes for less precise (albeit faster) alignment. I wish I had a chronograph available, as the long polygonal-rifled tube should provide greater-than-average velocity due to superior gas sealing, despite some fractional losses through the gas ports. The pistol shot approximately four inches above point of aim from my hands.
After this drudgery was over, shooting rapid pairs of shots showed me the inherent potential of this collector’s item. Recoil is, as one might expect, mild. The generous butt section, steel construction, relatively light slide, gas delayed system and smallish 9x19mm round combine to make the GB pleasant to shoot. In addition, the heat generated by the expansion chamber system is well-controlled, a distinct departure from the H&K P7, which gets pretty hot in rapid fire strings after just three eight round magazines fired.
The size of the GB means that very few people will want to opt for it as a concealed carry piece. It is thick, long overall and has a longish butt section, making it a challenge even for those of us used to carrying full-sized service pistols.
The last street retail prices of the Steyr GB in the late 1980's were in the upper $500 range, which was on par with a SiG Sauer, but more than either the Glock 17 or the Beretta 92. Despite some advantages of simplicity of operation and parts count, time has passed the design by and Steyr no longer provides technical support, spares, or magazines (these cost well over $100 each in January 2010). While the GB is an accurate pistol, it is something one should (mostly) relegate to the status of Safe Queen, which is sad. It sure is fun to shoot!
Copyright 2010, 2015 by David Tong and/or chuckhawks.com. All rights reserved.