A Fair and Balanced Overview of the Glock Pistol
By David Tong
At the time of writing, Glock, Inc. has posted a 36% increase in sales over 2007, according to the National Shooting Sports Foundation. Now, it’s no secret as to why these pistols are so popular, though I thought I would examine them in greater detail to see just how close to perfection they really are.
Prior to the introduction of the Glock Model 17 in 1985, other manufacturers had toyed with the idea of the use of advanced polymers for firearms parts, most notably Heckler and Koch’s P9S and VP-70 series pistols of the 1970s. Earlier pistols primarily used plastics for stocks (grips) and these can be seen in the 1930s Walther PP and PPK, as well as the hard rubber grips found on certain Colt 1903 hammerless .32 ACP and .380 ACP pistols.
The H&K P9S used a trigger guard/front strap molding and a plastic wrap around stock, thus the shooter never touched anything metal when grasping the pistol. Coming from Germany, this is unsurprising, as it does get cold there in winter and the advantage of having a thermally neutral feel when it’s below freezing is a plus.
The VP-70 went further, in that the entire grip frame housing the trigger, magazine and lower fire control pieces was of plastic. This rather ungainly, 19-shot, DA-only auto was primarily a selective-fire machine pistol, meant to be used with a detachable shoulder stock and fired in short bursts, but a civilian VP-70Z version was available for a short time in the U.S. This pistol, with required steel reinforcements and slide rails, was the first pistol to use plastics in a big way.
Let us face one fact squarely here; despite the many positive attributes of the polymer frame, its primary advantage to a manufacturer is cost control, because it is far easier to build injection molds and mold plastic than it is to investment cast and/or machine steel and aluminum, which is far more labor and tool intensive. Long gun makers have faced this same issue, so despite non-traditional aesthetics, the proliferation of plastics in firearms production is here to stay, as manufacturers try to expand market share while controlling cost.
Gaston Glock was not originally involved in firearms. He had contracts to supply the Austrian military with entrenching tools and knives that were partially constructed of lightweight polymers. He decided to enter a competition in the early 1980's for a new Austrian service pistol and the rest is history. The G17 went on to become a worldwide favorite among law enforcement due to its lightweight, simplicity and durability under extreme use and abuse.
The proprietary polymer used in Glock pistols does not have glass strands in it and Glock explains that this is to provide integrity under extreme cold. While I am not familiar with the exact formulation, in feel the receiver’s injection molding feels like a combination of nylon and polyethylene plastics, as there is some flex to the frame when grasped hard. This may provide some reduction in felt recoil, as its fans suggest. I believe the pistol's decreased subjective recoil is primarily a function of the relatively wide and flat frame cross-section that fills the web between thumb and forefinger, spreading recoil force over a larger surface area.
The pistol’s metal parts are protected by a process known as Tenifer. It essentially closes the metal pores with a surface hardening crystalline structure over Rockwell 60c, close to diamonds, and a non-reflective black coloring is added to the mix. Tenifer is considered to be the best service pistol finish available on the market, as it is rust-resistant to the extremes of available testing modalities (more so that stainless steel), durable against normal wear and holster presentations and does not decrease operating tolerances when applied.
The pistol’s near legendary reliability is the result of several design factors. First, the narrow slide rails, on which the slide reciprocates on the frame rails, offer minimal space for foreign matter such as oil, sand particles and powder residue to collect. The rails themselves are very hard, thin steel parts that are molded integrally into the frame. Both the slide and frame rail surfaces are so hard that that a Glock pistol can operate completely dry, which is a boon in dusty, sandy or extremely cold environments, where the use of conventional lubricants can attract dirt or freeze solid. Glock uses a copper-based “anti-seize” grease on the rear of the slide rails as a break-in lube, which is supposed to be left in place during initial shooting.
Secondly, the polymer frame is recoil-resistant and extremely durable. It has come in three generations thus far, with a fourth “Rough Texture” variant of the third generation frame just debuting at time of writing. These changes are primarily distinguished by the addition of raised checkering (Gen. 2) and finger grooves and accessory rail (Gen. 3). While it does not have the tensile strength of steel or even hard-anodized aluminum (more on that a bit later), normal recoil forces are resolved by the plastic material and by the steel locking block in the frame, so frame failures due to recoil alone are nearly unheard of, even under very high round counts (100,000+).
The other thing that increases the reliability of the system is the Company’s use of larger than normal chamber dimensions and extensively relieved feed ramp throats from roughly 4-to-8 o’clock. Glock magazines provide an adequately nose up attitude to the cartridges, but the company still believes that this wider and deeper feed ramp is essential to provide reliability under lots of shooting and extreme conditions.
While there are many anecdotal stories about the Glock being able to digest thousands of rounds of ammunition without feed failure, there are also reports about out of spec ammunition being fired with catastrophic results to the pistol and sometimes resulting in serious injuries to the shooter. Known colloquially as “kaBOOM's,” or “kB!” for short, the evidence gathered so far has exonerated Glock. (No pistol can be fired safely with over pressure ammunition or a blocked barrel. -Editor.) No less than H.P. White Laboratories has investigated these accidents and they are perhaps the foremost forensic firearms testing lab in the country, if not the world. In every instance, they have ruled the culprit to be ammunition related.
What I remember from experience over 35 years, however, is that very few semi-automatic pistol designs have experienced like detonation issues and this is where the plastic frame, despite its many other advantages, may play a role in the injuries sustained by shooters. A typical pistol of steel or aluminum receiver construction, if the barrel itself had a similarly-heavily throated, SAAMI-standard diameter chamber, would typically not be destroyed in such incidents. Usually these older pistols would simply vent the powder gases down the magazine well, as well as out the ejection port, perhaps destroying the magazine and the stocks, but without causing any serious injury to the shooter.
Glock itself is adamant about not using lead-bulleted ammunition in their polygon-rifled barrels, due to lead stripping ahead of the chamber. This is a potential source of excessive pressure, as the lead builds-up at this point of peak pressure. .40 S&W chambered pistols have experienced the majority of the problems. The .40 is, of course, prevalent in American law-enforcement circles.
Bullet setback (usually caused by repeatedly loading cartridges from the magazine into the chamber without firing) can also dramatically increase pressure. Both Federal Cartridge and Winchester have gone on record stating that their ammunition is safe against bullet setback for two loadings from the magazine. In addition, Federal quietly increased the web thickness of their .40 brass in 1995, which presumably corrects what Federal saw as a potential problem in this caliber.
Having said all this, to be fair, all of the polymer framed pistols currently being sold have had similar incidents of catastrophic destruction, including the HK USP, the Springfield XD and the S&W M&P. Perhaps there is something to the idea of retaining a machined metal frame in one’s hands, despite the weight penalty. Thus, while it is important to inspect your carry ammo no matter what pistol you use, I think it is that much more critical with a polymer-framed pistol.
The pistol’s shooting dynamics have attracted tens of thousands of shooters, due to its simplicity of operation. Somewhat like a DA revolver, the Glock pistol is a so-called “point-and-pull” weapon, because there are no external manual safeties to remember to switch off before it can be fired. In addition, the relatively short stroke, quick resetting Safe Action trigger somewhat resembles a two-stage military trigger in feel, because the trigger fully cocks the striker before releasing it for fire. This has endeared it to many single-action autoloading pistol shooters, because the system offers a consistent short press for each shot.
Those of us who are used to this sort of trigger usually do well with it in rapid fire drills. In slow fire, the Safe Action trigger is a bit of a hindrance, although not nearly as bad as typical double-action-only pistol triggers, because the trigger travel is longer than that of a single-action pistol. In the slow fire shooting that I have done with G17's, G23's and G21's, I have found Glocks to be only “combat accurate,” with about 70% of my shots inside a 4” x 2” rectangle at 25 yards. (My G19 yields similar results, typically putting its 15 rounds into a 4.5"x4.5" square at 25 yards. -Editor)
One primary advantage of the Glock striker fired design is that it typically has a lower bore centers than older designs using an external hammer. (The bore center is the distance between the barrel’s center and the long axis of one’s hands and arm bones.) This provides greater control under rapid fire and a softer recoil sensation than one might expect in such lightweight arms.
One final point about the Glock design is that it can be unforgiving of careless gun handling. Keeping one’s finger on the side of the frame (out of the trigger guard) during the draw stroke and while returning it to its holster is a must with any arm, but especially for one with the manual safety set in the face of the trigger. On the other hand, the Glock design incorporates very secure firing pin and sear blocking drop safeties that positively prevent accidental discharge if the gun is dropped, even from great heights (such as out of an airplane) onto a hard surface. When at rest, the striker is not fully cocked, another safety advantage. In addition, because the Glock's three safeties are all "automatic," there is no need for a conventional thumb safety that can be left on when it should be off, or off when it should be on. Real firearms safety is, of course, in mind of the shooter. I would, however, suggest following the Company’s advice and use only factory loaded, jacketed bullet ammunition for both practice and self-defense.
In perspective, one cannot help but admire the Glock design for its low parts count, operating simplicity, high capacity, great durability, reliability and lightweight. If imitation is the highest form of flattery, practically every other major handgun manufacturer has flattered the Glock!
Copyright 2010 by David Tong. All rights reserved.