Who said that all striker-fired handguns with 9mm chambers have to have polymer frames. No one I know. The popularity of the Glock 17 pistol and the other polymer-frame striker fired pistols on the market today has probably sparked that thought in many of us. Rock Island Armory has introduced the STK100, an aluminum-frame striker-fired 9mm pistol. It’s already a popular choice. The Rock Island STK100 – Knock-Off or Brand New? Although it looks similar to the full-size Glock, there are important differences. It is about 5 ounces heavier and has a distinctly grip-heavy balance. Its steel slide has seven weight-reducing ports on its top and sides. (Photo by Alex Landeen). A second difference is that the grip angle of the STK100 is the same as the M1911. Many shooters find that Glocks point high, while the 1911 is a dead on. It takes time to learn how to point the pistol downward for those of us who have had a Browning P35 or 1911 as our first pistol. The STK100’s aluminum frame, which is stronger than most pistols made from polymer frames, is a third difference. The STK’s aluminum frame is more rigid than most pistols with polymer frames. It doesn’t flex during firing like most polymer frames. While most people don’t notice the flexing, it can cause instability that can affect accuracy. This phenomenon is most relevant for competitive events such as Bullseye. The aluminum frame’s effect on recoil is the last major difference. All other factors being equal, heavier guns tend to have less recoil and are able to return to target a bit faster. This is important for IDPA matches and shooting steel. It also serves as self-defense. The STK has fewer differences than other striker-fired pistols. This is due to the larger triggerguard that allows for gloved fingers. It also has an extended beavertail at its rear. It also has a two-piece “clamshell frame” that is held together using Allen-type screws. The STK100 also has a built in mounting platform that houses the rear sight. (Photo by Alex Landeen). It took only a few minutes to remove the plate from its mounting bracket, loosen it, and then install the Vortex Venom red dot. The Venom’s rear sight is also clear. It has two white lines that can be aligned with the front sight to create an accurate sight picture in the event of an equipment problem or sudden battery failure. These features make the STK100 a Glock pattern pistol with a unique personality. Although it looks very similar to the Glock 17, it has significant differences in terms of materials and how it handles recoil. This makes it stand out from the rest. However, some of its internal parts have the same specifications that parts from the G17. This means that you might be able use existing parts from the Glock to customize the STK100. But make sure to check with a gunsmith before you do this. (Photo by Alex Landeen). This is a bit paradoxical because the STK100 is unique enough to make it unique enough to use custom parts for a Glock 17. If installed, it would be even more special! On the Bench Before I go to the range, I always place the firearm on my workbench to evaluate it. I like to inspect the quality of the manufacture and remove any packing oil or firing residue. I am especially cautious with firearms from overseas. Because they are often shipped via sea, they are often coated with large quantities of oil or grease to prevent rusting. After cleaning and inspecting the gun, I lightly lubricate the gun and then take it to the range. Overall, the STK100 was of good quality. There were some sharp edges at the forward edge of the dust cover accessory rail as well as at the rear corner the magazine floorplate. There were also some very fine manufacturing marks on the grip’s upper rear portion. (Photo by Alex Landeen). The trigger pull of the 5-pound gun was stiff and gritty. This can be corrected with a little gunsmithing. These findings are not show-stoppers. The aluminum frame was well-made and fit perfectly. The slide’s smooth operation and excellent machining quality are just two of the many things I was impressed with. Three Rock Island STK100 load types were used for testing. These were Norma’s 108-grain MHP and Hornady’s 135–grain +P critical duty, as well as Armscor’s 124–grain FMJ. The Armscor ammunition was used to sight in tactical drills. The other two were used to test accuracy and velocity. (Photo by Alex Landeen). After the optic was sighted in accuracy tests were performed at 15 yards. This is the distance most civilians would normally shoot in a critical situation. Both duty loads were accurate. The Norma load shot an average five shot group of 2.19 inches. The Hornady’s average group was 2.66 inches. Both loads were accurate enough to be used for tactical purposes at reasonable distances. The Norma load averaged 1,131 feet per second (fps), with a narrow extreme spread of only 29 fps. This translated to an average energy value of 307 feet-pounds (fpe). This is significantly lower than the 413 fpe listed on the box. (Photo by Alex Landeen). The Hornady Critical Defense loads produced 1,065 fps. With an extreme spread rate of 23 fps. This resulted in a muzzle energy average of 340 fpe. It is clear that the gun’s accuracy and velocity are consistent. It also speaks to quality of these duty loads. Scenario-Based Tactic Drill This scenario-based tactical drill was performed at 10 yards with a picture target purchased from Law Enforcement Targets. Law Enforcement Targets is owned by Action Target. This was the scenario: You are a young man just starting out in life. You have moved into a basement apartment below street level to save money. The entrance is located behind the concrete foundation wall, just like many basement apartments in large older cities. From your front door, a handrail leads up the steps to street-level. The handrail connects to a railing that runs along the sidewalk. A potential armed robber appears about ten feet from the steps. He points a 1911 at you and turns towards you. He is using the handrail and railing as protection for vital organs on the left side of his abdomen, shoulder, and chest. (Photo by Alex Landeen). You respond by moving to your left and firing two shots to his right side. In my five repetitions of drill repetitions, all 10 shots were fired on the body and missed at the railing. This prevented any deflections from railing. My Competition Electronics shot-timer measured that the average time was 5.09 seconds. Eight shots were in the chest. One shot strayed into robber’s right arm. The tenth shot went high, hitting just under robber’s chin. The trigger was pushed hard, causing both hits to be outside the upper chest. Important Reminder: The trigger was too hard to pull. This was due to the case being too large. The brass cooled in about 10 seconds and was easy to eject after manually cycling the slide. Additionally, the gun had fired more than 100 rounds without cleaning it. The stoppage could have been caused by a combination powder residue and case expansion. All other rounds of test ammo performed flawlessly. The stoppage can therefore be interpreted as a temporary occurrence that reminds you to clean your gun and lightly lubricate it after each use. (Photo by Alex Landeen). Standing Out The Rock Island STK100 cannot be considered a knockoff. It has its flaws, as with many new models, but it is sound, well-made, and accurate. It will be tested over time to see if it can compete in a market saturated with polymer products. Many people believed that a “plastic gun”, like the Glock 17, would never be made in America when it first appeared. Armscor.com has more information. Rock Island Armory STK100 Specifics Caliber: 9mm
Barrel: 4.5 inches
Overall Length: 7.91 Inches
Weight: 1.8 pounds (empty)
Grips for Aluminum
Sights: Tenon front cut, fixed rear
Action: Striker-fired semi-auto
Finish: Black anodized
Capacity: 17+1
MSRP: $599. This article was originally published by Combat Handguns January/February 2022. Subscription is available in print and digital editions at OutdoorGroupStore.com. Or call 1-800-284-5668, or email [email protected]. Continue Reading Search The post Heavy Metal Striker – Testing the Rock Island Armory STK100 appeared originally on Personal Defense World.
