The gun industry would never be the same after the Austrian company Glock introduced the Glock 17 to the United States in 1986. Since then, law officers worldwide have found them in their holsters, and competitors have desperately tried to introduce products to rival the Glock’s success.
As an armorer, I’ve completely disassembled and compared the striker-fire technology in competing products, and have seen that many polymer pistols are similar in function and concept to the Glock. New takes on the polymer design continue to be introduced, but the Glock has remained basically unchanged. Glock has added models in various calibers and changed the frame to accommodate customer’s needs for concealed-carry or grip comfort, but the basic formula remains.
The Glock family includes large-frame pistols, such as the Glock 20 and 21, introduced in 1990. The larger frame proved necessary to accommodate the cartridge size in the double-stack 13-round magazine. Unfortunately, the company sized these large-frame Glocks in proportion to the other Glocks to maintain the gun’s signature feel and handling characteristics. Some users have found them challenging to properly grip and uncomfortable to shoot. Because many officers are returning to the .45 ACP, the introduction of the Glock 21 SF (Slim Frame) is a strategic move for the company.
The Glock 21 SF features three obvious modifications aimed at making the Glock a more universal pistol. The first is an optional picatinny rail system in place of the single-notch Glock rail seen on some second- and third-generation variants. The Glock light works well with the Glock rail, but many users choose to incorporate illumination tools such as those from Surefire, Insight Technologies and Streamlight. Certain models won’t attach properly with the Glock rail systems, however, so the addition of a picatinny rail should be well received.
For some in law enforcement, it’s been a consternation that Glock hasn’t made a left-handed or ambidextrous version until now. (I know of a few departments that choose to alter certain aspects of training to accommodate the Glock’s right-handed magazine release for left-handed magazine changes.) With a special cut at the front of the new Glock 21 magazine and an altered magazine-release assembly, magazine changes are now easier for left-handed shooters. Current Glock 21 owners will face one drawback, however—their old 21 magazines won’t function in the new 21 SF model. The 21 SF mags will work in all Glock 21 pistols, however.
The biggest modification to the 21 is felt rather than seen. To reduce the girth, Glock slimmed down the grip with a noticeable reduction of material mass at the back strap. Those with smaller hands, or fans of single-stack pistols like the venerable 1911, will consider this alteration an improvement.
During evaluation of the 21 and 21 SF on the range, I noticed this grip modification changed the shooting experience. A former law enforcement officer of Portsmouth, Va., and I ran hundreds of rounds of popular self-defense loads from Federal, Winchester and Remington. Shot at Blackwater’s indoor Talon test range and an outdoor range, both Glock 21s performed well. The change in the 21 SF’s frame size became immediately evident for each of us. I felt a greater sense of control, resulting from a higher grip in relation to the bore axis and more frame contact in my hand with a reduced grip radius. As a primary 1911 shooter, I also noticed a steeper grip-to-frame angle, which made point shooting quite natural and quick.
The Glock’s simple design and easy maintenance has contributed to its success in the law enforcement community. Of all the pistols maintained in my armories, the Glocks have been in for repair the least. These were primarily for worn springs (often a broken trigger spring or a slide-lock spring), improper assembly and excessive lubrication (see a Glock owner’s manual for specific lubrication points). The used Glock 21 we had on hand for range testing had more than 10,000 rounds known to have been shot through it, with little if any care. During this test, it twice failed to return completely in battery. After inspection, we determined the recoil spring had lost tension and caused the slide to return sluggishly. These two failures were the only two we experienced during testing of each pistol.
Sights were right on for each pistol—point of aim and point of impact. The used Glock 21’s trigger required 5 lbs. of pressure before the striker was released to fire the cartridge, true to the factory-installed 5-lb. connector. The new 21 SF required nearly 7 lbs. of pressure for the same result, possibly because it was a new specimen. Pleasing to some, several aftermarket 3.5-lb. connectors are available and should be installed by a Glock-certified armorer. Departments can also get 8-lb. and 13-lb. connectors from their Glock armorer, or order pistols equipped with them.
Considering the wide usage of Glocks and the obvious benefits the new Glock 21 SF provides, it’s very likely similar features will become commonplace among other existing Glock models. Don’t be surprised if your agency puts one on your duty belt.