STI Duty One 9mm
It could be said that the Browning 1911 pistol has evolved more than any other design. The operating principal remains the same, but alternate configurations have been applied to nearly every facet of its execution. In fact, it is now commonplace to buy over the counter what not long ago would have been considered a full-blown custom pistol. We all know about beveled magazine wells, frame checkering, undercutting the trigger guard for a higher grip, high-arch memory groove grip safeties, extended magazine releases, aluminum triggers adjustable for overtravel, light rails on the dust cover, extended and/or ambidextrous safeties, checkered slide stops, skeletonized hammers, titanium firing pins, front and rear serrations on the slide, weight reducing slide cuts, lowered and flared ejection ports, full length guide rods, bull barrels, multi-spring recoil systems, external extractors, spring-loaded internal extractors, ramped barrels, adjustable sights for target, adjustable low-mount sights for carry, light-gathering-filament sights, or self-illuminating modules for front and rear sights.
A few years ago we would have called them factory customs, but that term is obsolete. The most distinguishing characteristic of the test gun was that it was chambered for 9X19 shells, aka 9mm Parabellum or simply 9mm. The $1299 STI Duty One shipped with and fed from a 9-round MetalForm-brand single-stack magazine. Gun Tests accepted an offer from Houstons Top Gun Training Center (www.topgunrange.com) to conduct the test indoors. The range was under renovation, so while the ActionTarget.com folks were working their magic on one shooting bay, they set up targets at the other end of the building. Test distance was 15 yards and Black Hills ammunition was used exclusively in the tests. For break in they opened a case of 124-grain FMJ ammunition packed in blue boxes (remanufactured). Both the 115-grain FMJ and 124-grain JHP rounds were new manufacture (packaged in red boxes). They brought in a portable shooting bench and went to work firing five-shot groups. Here is what they learned.
STI International, located in Georgetown, Texas, is one of the more accomplished small companies that produce and sell custom components as well as completed guns. The Duty One is a single-stack 1911 with several competition-grade modifications plus a dustcover machined as an accessory rail. A tour of the STI Duty One from the ground up begins with a beveled magazine well. To either side of the grips were wide-gauge composite panels held in place by Allen screws colored dark blue to blend with the rest of the pistol. The panels featured scrolled stippling top to bottom (save for the STI logo), and a dished relief to enhance access to the magazine-release button on the left side. The front strap was treated to 30-lpi checkering. The backstrap featured a flat-profile mainspring housing checkered at 20 lines per inch. Above the mainspring housing was an oversize grip safety with raised surface to ensure contact with the shooters hand. Thumb safeties of equal width platforms on both sides of the frame were applied.
The magazine release was brief but effective. It was also drilled and tapped should the operator prefer an extension. The hole left in the release was not necessarily an eyesore because it managed to offer a finished look. The bottom outer radius of the trigger guard was relieved in the manner one might refer to as dished or concave. If it were a barrel it would be called fluted. They thought it was a nice visual touch and perhaps an attempt to reduce weight. Nevertheless, the Duty One was heavy. Aside from the extra material at the dustcover, much of the STIs weight could be found in its bull-barrel system. Keep in mind that the smaller 9mm bore leaves behind a heavier barrel than would a 45 caliber model. Another source of weight was likely the slide. The staff reported that the width of the slide as viewed from behind the grip was larger than those found on other guns. Some members of the staff thought it was distracting. Atop the slide was a set of (Richard) Heinie sights. Perfectly matched, their profile was streamlined. Sans indicators such as white dots, the faces of each sight front and rear were lined to diffuse glare. Clarity of the sight picture was superb.
The recoil system was a multi-spring and plunger unit referred to as the STI Recoil Master. Compared to a simple coil spring over a solid rod, this design looked more like a shock absorber that might be found on a race car. For a quick look at the frame they could simply pull back the slide to match the breakdown relief and push the slide-stop pin out from right to left. But if they wanted to remove the barrel, the use of a special jam, or stop, was necessary. STI supplies a plastic part that locks the outer spring in place and allows the unit to be removed as one. The preferred method is to lock back the slide and snap on the jammer. But it is also possible to remove the top end first and use a thumb to push the assembly forward far enough so that the inner rod is exposed and the jam can be applied. Naturally, the jam only covers about 180 degrees of the Recoil Master. Rotating the assembly so that the open side is facing you as the Recoil Master is pulled out will help get it past the yoke on the slide.
At the range they found that the STI Duty One recoiled less than our other guns. This could be attributed to the Recoil Master or merely the extra weight. They liked the 4.5-pound trigger, too. The wide grip panels helped fill the hands and as previously noted the sights were very clear. They began collecting accuracy data by firing the remanufactured Black Hills 124-grain FMJ rounds. Accuracy was consistent with groups ranging in size from 1.3 to 1.6 inches across. The new manufacture Black Hills 115-grain FMJ rounds were even more consistent. Groups measured 1.4 inches, 1.6 inches and then 1.5 inches. But here is where the test of the STI Duty One came to a halt. During the third group of 115-grain FMJ rounds they began to see the empty cases being ejected with less and less vigor. With the gun emptied they worked the slide and discovered it was having difficulty moving, especially just before going into battery. They removed the top end to inspect the frame and slide and discovered that the ejector was bent. The ejector on a 1911 design is mounted on the platform above the grip just rearward of the magazine well. It sticks up about one-quarter inch and rides inside a channel cut into the bottom of the slide just to the left of center. As the slide moves rearward carrying the shell from the chamber, the ejector, which simply put amounts to being a poker, punts the spent shell out the ejection port. This clears the way for the extractor to pick up a fresh round from the magazine.
Why didnt they simply didnt bend the ejector back into line. They decided that doing so in a precise manner would have been difficult at best. As it was, the bend prevented them from replacing the slide without damaging additional parts. Above all, the main concern was why did it happen to a gun that, up until failure, was shooting lights out? We did observe that the ejector on our STI Duty One was substantially longer than other pistols. The ejector on the STI pistol protruded about 0.38 inch. Was this by design or was the wrong part installed? For answers and a warranty repair, they returned the pistol to STI. The STI Duty One was received at the factory on Friday, one week prior to Christmas Day, 2009.
They had the pistol back in their hands the following Wednesday morning. They returned to the range to finish the testing. This included shooting more groups and launching rounds over the sensors of the Oehler chronograph. Function was now 100%. They expected nothing less because the enclosed work order, (signed and dated), said that the pistol had test fired 45 rounds successfully. The ejector had been replaced and several other points had been addressed. These included polishing the feed ramp, tuning the safeties, refinishing the breech face, and hand-fitting a fresh Recoil Master. In the magazines view this followed reasoning that machine parts are interdependent and must be in tune with multiple components. They concluded that the test pistol simply received the 10,000-round tuneup a little early.
On the telephone, they learned that the original ejector was indeed too long. After servicing, the tip of the extractor now reached across the magazine well about 0.27 inches. This was a reduction of about one-tenth of an inch. No further malfunctions were experienced. Beginning where they had left off in our bench session, accuracy with the 115-grain FMJ ammunition was still in the 1.3-inch to 1.6-inch range with the new extractor in place. Firing the 124-grain jacketed hollowpoints, the STI Duty performed slightly better with groups measuring just less than 1.4 inches across on average.
Gun Tests Said: The STI Duty One is obviously aimed at the law enforcement market. It benefits from the addition of an accessory rail, and like so many STI products incorporates features learned in the rough-and-tumble world of competitive Practical Shooting. Formed to fit low in the hand, the Duty One displayed a muzzle-heavy bias that smothered recoil. This low-profile-finish, sophisticated pistol was pleasing to shoot. An early problem was solved quickly by attentive customer service.