The 10mm pistol cartridge was developed to fill the gap between 9mm and 45 ACP firepower. In 1989 its popularity was spurred by the FBI choosing 10mm as its favored caliber. At the time, Colt successfully chambered a 1911 for 10mm, the Colt Delta Elite. Smith & Wesson tried to adapt its line of semi-automatic pistols as well. Durability became an issue. But then pistol makers found out it was easier to increase the strength of their 9mm fleet to handle another round developed almost concurrently, the 40 S&W round, rather than tool up to withstand the more powerful 10mm rounds. We could resort to revolver jargon and refer to 10mm ammunition as 40 Magnum. That’s because both 40 S&W and 10mm ammunition share the same diameter bullet, but the 10mm case is 0.140 inch longer.
Time has not quite eclipsed the standard 10mm round, but it is now decidedly less popular than the 40 S&W it sired. The big reason: the 40 S&W delivers noticeably more power than the 9mm, but the larger high-velocity round can still be packed into same frame as current 9mm pistols with little structural change.
This brings us to our current roster of test guns. The Ruger SR40 began life as a 9mm pistol, and since our test of the SR9 in the December 2007 issue, a compact version is now available in both calibers. Likewise, the roots of the Glock 23 Gen4 can be traced to the 9mm Model 19, which itself was the compact version of the G17 service pistol. The Springfield Armory XDM40 Compact is somewhat of a hybrid with characteristics of both a compact and full-size pistol. Developed from a foreign-manufacture 9mm service pistol, the XDM Compact offers a shortened grip for better concealment and a full-length 16-round magazine that includes a grip extension. Our fourth pistol is a true subcompact, and it shoots the same bullet as our other test guns but from a longer case that packs more powder. The Glock Model 29 chambers 10mm ammunition, from which 40 S&W was developed. Since the 10mm originally lost favor due in part to its recoil, we wondered how much we’d like shooting the round in such a small package as the G29.
How We Tested
Unlike our recent test of 1911 45s, wherein all three guns were nearly identical, these test guns each had their own personality and demanded slightly different shooting techniques. Accuracy data was collected from the 25-yard bench utilizing multiple sandbags to support the guns and stabilize the shooter’s hands and arms. Test ammunition for the 40-caliber guns consisted of an aggressive defense load, a budget hollowpoint, and a high-quality remanufactured target round. The Pow’R Ball 135-grain rounds from the Glaser line of Cor-Bon ammunition featured a polymer ball held inside the tip of a jacketed hollowpoint. The ball smoothed out the profile of the cavernous hollowpoint to ensure feeding. The 180-grain Remington JHPs were sold in bulk 100-round boxes. Our third 40 S&W round was the 180-grain FMJ round from Black Hills Ammunition. We also used 135-grain 10mm Pow’R Ball ammunition in our test of the Glock 29. All four guns were able to cycle these rounds without error. In addition our G29 was tested with Remington 180-grain MC (metal case) rounds and 180-grain Federal Hydra-Shok jacketed hollowpoints. Not a single malfunction spoiled our tests. We should note that despite firing bullets of the same diameter, the 10mm and 40 S&W cartridges are not interchangeable in pistols.
Let’s find out what each gun has to offer.
Ruger SR40 BSR40 40 S&W, $525
The Ruger’s SR series pistols strive to bring the ergonomics of a slim single-stack pistol to a double-stack design. In terms of actual dimensions our SR40 was narrower than any of the three 1911 single-stack pistols tested in the September 2011 issue, including Ruger’s own SR1911. Yes, this can be adjusted by changing grip panels on the 1911s, but in addition the bore line of the SR40 sat lower in shooter’s hand. There was also about one full inch of frame overhanging the web of the shooter’s hand, helping to fight recoil.
Lighter than steel or aluminum, the use of glass-filled nylon for the grip frame made the SR rigid and hard. The checkered side panels felt as though they were machined and not the product of a mold. Inside was a wide-body magazine carrying 15 rounds. The backstrap included a reversible panel made from moderately hard rubber, which slid into place from the bottom of the grip and was anchored by a solid pin. One side left the backstrap flat, and the other side extended the grip to form an arched mainspring housing. Magazine-release buttons appeared on both sides of the frame, and we noticed a marked reduction in width leading from the web of the hand to the trigger on both sides. But we found both the ambidextrous safety levers and the slide-release lever (left side only) difficult to use. It was easier to raise the safety into the Fire position than it was to lower it to Safe. We had to change our grip to engage the safety, and this meant leaving a hollow space between the gun and the inside of our grip, at least momentarily. To charge the pistol, we chose to pull back on the slide to allow the stop to fall away and release the slide.
The frame included a full-length dustcover with a single-groove accessory rail ahead of the trigger guard. The slide carried a three-dot sight system dovetailed into place front and rear. The rear sight was windage adjustable by drift only but did offer click-adjustable elevation adjustment. The SR40 is available with a stainless steel slide, but we chose the alloy steel slide for its stealth Nitrodox Pro black color. All the SR models, both compact and full size, cost $525 MSRP. In fact, there has been no change in price since 2007.
Elsewhere, however, we noticed changes from a 2007 9mm model, including the addition of a loaded-chamber indicator. That consisted of a 1.25-inch steel bar located atop the slide between the ejection port and the rear sight unit that cammed upward when a round was in the chamber. Spring action on the indicator was very light so as not to damage the case rim. Natural in color with the words LOADED WHEN UP boldly engraved, we think experienced shooters will welcome its tactile capability for warning or reassuring the operator. But visually, it can be a turnoff.
Another difference from early models was the Glock-style compressible safety lever in the face of the trigger. A change to a “D”-shaped magazine-release button with checkering was also apparent. Of more importance was that the 40-caliber slide was wider than the 9mm component by about 0.05 inches across. This was to provide greater strength. In addition, the slide stop/takedown pin was longer and its rear tip curved into the frame for more secure location.
Takedown of the SR40 was simple. Remove the magazine and empty the chamber. Next, lock back the slide. The slide stop acted as the takedown pin. Its right-side tip was flush with the frame. This was important because inadvertently pushing the slide-stop pin during cycling, especially when the slide is being worked by hand, can push the pin ajar and create a stoppage. There was little or no danger of that happening with the SR40. With the slide locked back and the slide-stop pin removed, the proper procedure should be followed. The wrong way is to release the slide and press the trigger as the slide moves forward off the frame. The right way is to reach in and push down on the ejector. With the ejector in the down position, the trigger does not need to be engaged to remove the slide.
Beneath the slide we found a captured recoil assembly with a single flat-wire spring. The guide rod was polymer, but we liked the steel plate on the end that butted up against the barrel. Reassembly begins with applying the top end to the frame, locking it back and pulling the ejector upward. If you do not pull the ejector back into position, the trigger will not reset. After seating, the slide-stop pin the slide can be released to close the action.
From the bench we learned that the slower we pressed the trigger the more we were aware of its imperfections. Some gunsmiths say this is a result of interaction with the magazine disconnect function. Our best accuracy was achieved when we pressed the trigger in one continuous motion rather than trying to find the break point. In fact, the Ruger SR40 was the top performer firing the Remington 180-grain hollowpoints, producing a 1.8-inch average from the 25-yard line. Its favorite round was the Black Hills 180-grain FMJ, and we nearly managed a five-shot average of less than 2.0 inches across firing the Pow’R Ball rounds. In our opinion the saving grace was the SR40’s ergonomics. The way the SR40 molded to our hands we could drive the sights without losing our preferred grip during recoil.
Our Team Said: Remarkably underrated, this is the plastic gun for people who don’t like plastic guns. Its slender profile makes it more controllable than most high-capacity guns, and it’s a good candidate for concealed carry, too. We liked having manual safeties even if they weren’t perfect. Though not match grade, we thought the trigger was predictable with a reasonable sense of takeup and overtravel.
Springfield Armory XDM 3.8 Compact XDM9384CSHC 40 S&W, $769
The “M” series introduced several improvements to the XD series pistol. One was the ability to remove the top end without having to press the trigger. A loaded chamber indicator atop the slide operated much the same way as the Ruger, but it was smaller, not labeled, and altogether less obvious. The XD-series pistol, which began life as a law-enforcement sidearm in Croatia, already had a visual and tactile reminder when the action was cocked. That would be the pin that extended from the striker through the rear face of the slide. Thanks to the rear sight now seated flush with the back of the slide, the XDM models offer increased sight radius. Both models offer cocking serrations front and rear, but the XDM slide was better looking, we think. The new trapezoidal profile to the slide also erases the need for a special channel to accommodate moving the slide latch to its takedown position.
Despite having a shorter barrel than 4-inch Service models, our XDM 3.8 offered three slots on its accessory rail instead of two. The profile of the rail was squared to Picatinny specifications. Although many consider the standard XD to offer one of the best grips found on a polymer pistol, the XDMs offer a flatter profile on the side panels and a more natural curve to the backstrap. In addition, the XDMs come with three different-size backstraps marked I, II, and III (or, more simply, small, medium, and large).
Our compact model with its shortened grip housed a flush-fitting 11-round magazine. In addition, two 16-round magazines were supplied. These longer magazines arrived with a collar affixed to the magazine body that extended the backstrap to create a continuous full-length grip. To test the reliability of the extended magazines we loaded 16 rounds into the larger magazines and let them sit in our safe for more than 5 weeks. Then we oiled the gun and took it to the range for its first firing session. To date no malfunctions have occurred with this pistol regardless of magazine or choice of ammunition.
Takedown began with releasing the magazine, clearing the chamber and locking back the slide. To move the slide fully rearward the grip safety must be pressed inward. This is best achieved by letting the web of the hand take its natural position. With the slide locked back and latch turned upward, the slide lock was pressed, releasing the top end from the frame. The new-style slide lock was easier to use. The recoil system was the dual-spring plunger type. All steel and heavily built, the end that connected with the barrel was especially beefy, more than two-tenths of an inch thick.
The magazine well was sculpted with a helpful funnel-like contour. Magazine-release buttons were on both sides, and neither one was in danger of being activated unintentionally. But releasing the magazine from the short grip meant you had to get your hand out of the way. Releasing the longer magazine was easier, but reloading to either size magazine took a little care. Another thing to remember was to always depress the grip safety when racking the slide. Otherwise, the slide was blocked from a full-length stroke. The longer magazines and resulting longer grip made working the slide much easier. But with the magazine removed to clear the chamber, the stout recoil system combined with the short grip made it more difficult to pull back the slide. To improve overall handling, we sought out a grip extension for the shorter 11-round magazine. The first one we tried was a replacement basepad marked “XD by Pearce” that added a finger groove for the pinky. But we had to grind off the upper edge so that the magazine could fit smoothly in place. Subsequently, Pearce is offering the correct size basepads for XDM magazines.
At the range we found that our XDM Compact was the best performer with both the Cor-Bon/Glaser Pow’R Ball rounds and the Black Hills Ammunition, landing average groups sizes of 1.1 and 1.2 inches respectively. Each of these rounds helped us achieve the only sub-1-inch groups fired from the bench. Despite having a short barrel, the XDM Compact managed to drive the 135-grain Pow’R Ball rounds 1286 fps on average, producing 486 ft.-lbs. of muzzle energy, the highest registered among our 40 S&W pistols. In terms of recoil control, the gun didn’t squirm out of our grip. Rather, it seemed to nestle in our hands. We think this was because of the small circumference covered by the middle finger and thumb of the strong hand. Another key point of control was the ability to apply the right amount of pressure to the palm by replacing the backstrap to suit our hands. One of the best combinations for carry we found was to holster the gun with the short magazine in place, augmented with the Pearce grip extension. To balance out our rig, the longer magazine was carried on our weak-side hip. The supplied paddle holster did a good job of keeping the heavily laden 16+1 pistol stable on our belts. We think it was natural to interpret the design of this gun as a house gun with the big magazine in place, loading the short magazine for concealed carry.
Our Team Said: Testers said this one had versatility, accuracy, power, and style. Range notes included the word “Sweet” referring to the trigger. The XDM 40 Compact may cost a little more, but it comes in an airline-quality attach with a very good holster and magazine pouches. It’s a high-capacity house gun. Or, it’s a carry gun that when loaded with 11+1 rounds of 180-grain 40 S&W that weighs less than many eight-shot pistols. The simplicity of a standard 3.8 is likely a better choice for some, but we think the Compact “convertible” is hard to beat.
Glock 23 Generation 4 40 S&W, $649
The middle size Glock 19 has been around long enough so that it is nearly invisible. We rarely see it in slick magazines unless the article is about off-duty guns. The standard Glock 23 is very much the G19 beefed up to support 40 S&W. But in doing so we think the standard G23 loses some of the 19’s nimble appeal. What the Gen 4 does for the G23 is slim down the grip, making it smaller without losing the structural integrity necessary for firing a heavier bullet in the neighborhood of 1000 fps. Magazine capacity was 13 rounds. With the grip slimmed down, there was enough space left to accommodate a selection of backstraps, of which two were supplied.
Before we go further, we should answer the question, “What happened to Generation 3?” According to Glock customer service, Gen 4 or Generation 4 is a nickname the company adopted after it became popular among consumers. What some refer to as the Gen 3, however, is the RTF2. RTF stands for “rough texture frame” and was distinguished by a surface pattern of small spikes molded into the grip. This pattern was to better serve operators who commonly wear gloves while in the field. Limited to law enforcement personnel only, the RTF2 pistols are now out of production.
The spikes that distinguish the Gen 4 texture from the RTF2 pistols are flat and less abrasive. Another characteristic of the Gen 4 was its magazine release that can be changed to the other side of the frame. The release button was seated flush on the sides protruding only at the forward edge of the grip. This made it necessary to rotate the pistol in the hand to release the magazine. The Gen 4 pistols also utilized a multiple-recoil-spring guide rod. The model designation SF or Short Frame (in this case meaning the distance from the trigger to the rear of the backstrap), will be going away in some models. That is because with none of the extra backstraps in place, the bare pistol will in fact be very close in dimension to an SF style pistol. Our G23 Gen 4 came with Glock’s night sights (a $50 upgrade) that we think provided a better overall sight picture that the stock units as well as illumination.
The method of holding the extra backstraps (marked M and L) was inconspicuous. The groove that holds the straps in place appeared ornamental and gracefully followed the lines of the grip. Located near the web of the hand was the trigger housing pin, which served to anchor the extra backstraps. An extra-length pin and a push-pin tool were supplied, so we didn’t need to use a hammer. One of the backstraps turn the gun ostensibly into a “Gen 3” pistol, and the other makes the grip larger still. You’ll need the long pin to properly seat the largest backstrap.
Without an alternate backstrap in place, the shooters in our group with the largest hands wore the Gen 4 like it was a glove. The larger backstraps may actually be of more use to shooters with thinner gauge palms. The key is to get a firm grip without leaving space beneath the hand. This better allows the shooter to isolate the trigger finger from the stress of holding the gun. Some shooters use the technique of releasing the trigger no further than the point of reset after every shot. But we felt that trigger feedback was somewhat vague and concentrating on finding the release point could distract the shooter from maintaining a firm grip. Given that the overall consistency of the trigger was very good, we think a slightly longer but consistent-length stroke of the trigger from shot to shot was more effective.
In terms of benchrest accuracy, the Black Hills 180-grain FMJ rounds were the best choice with five-round groups varying in size from 1.4 inches to 2.1 inches across. For some reason the G23 Gen 4 didn’t take to the Pow’r Ball loads. In our view the 180-grain rounds, which are more or less an industry standard for 40 S&W, seemed to be the best choice.
Our Team Said: Among serious competitive shooters, one of the most popular grip modifications to the Glock pistol is grip reduction. So we’re not sure how many shooters will actually choose to apply the extra backstraps. But we applaud the Gen 4 grip profile, which makes the pistol easier to handle and more visually appealing, too. It might be the improved grip that was helping us better cope with recoil or it might just be the new recoil system. This unit added weight below the barrel where it could work against muzzle flip. Or the multi-spring action may be spreading the recoil impulse over a longer period of time, thus changing our perception of how the recoil felt. Regardless, we liked this pistol because it provides the power of the G23 but carried more like the G19.
Glock 29 Subcompact 10mm, $637
We expected the 10mm Model 29 to be a handful, but we think there were two factors that actually made our test enjoyable. For one, today’s 10mm rounds have been refined so that the 20+ available commercial loads are more efficient and less harsh. Second, a key characteristic of the Glock pistol is that it does tend to flex and absorb shock. This was recently underscored when a few innovative manufacturers chose to produce Glock frames made from steel and aluminum. We had a similar experience firing a small steel-framed 1911 45 alongside a 45 ACP Glock 30SF.
The Glock was much easier on our hands. In a side-by-side test of the 30SF vs. our G29, we had to say that the 10mm recoiled sharper but with less torque, and the cycling process seemed to be over much sooner. What made the Glock 30SF more controllable was the oversized base pad that comes standard on this model. Adding a grip extension to the G29 would be very helpful, in our view.
Our G29 offered the standard Glock components. The magazine release was left side only. It was thin but taller than the one found on the Gen 4, and we liked its availability. We’d prefer the upgraded slide release over the flat sheetmetal tab that was difficult to operate. But you didn’t have to pull the slide back very far to release the catch and let it forward. The standard sights were low profile, but some shooters find the bold white underscore distracting.
Takedown and reassembly of the Glocks was very simple. First, clear the gun completely because the action must be decocked, and the only way to do this is to press the trigger. With the slide retracted about 3/8 inch, the locks on each side of the frame are pulled downward. The slide was then free to move forward off the frame. Sliding the top end onto the frame will reset the locks automatically. With the top end removed, we were surprised how much the slide of this 3.78-inch barrel gun weighed. The entire pistol was listed at about 25 ounces yet the full-size Model 20 with a 4.6-inch barrel weighed just shy of 28 ounces. For the sake of further comparison, the slide of the G29 with barrel and recoil system removed weighed the same as a model 30SF. The 45 ACP barrel itself was the only component that weighed less. Magazine capacity of the G29 was 10 rounds.
The 10mm G29 was the pleasant surprise of the test. The 180 MC rounds from Remington were preferred, delivering an average group measuring 1.3 inches across. The Federal Hydra-Shoks produced an average size group of 2.1 inches, and the Pow’R Ball rounds varied from 2.3 to 3.1 inches per five-shot group from support. We think shooting offhand would have been improved with the help of a place to put our pinky. The Pow’R Ball ammunition delivered 545 ft.-lbs. from the little barrel. The Hydra-Shok was more consistent, probably as a result of greater controllability. Generating less felt recoil, these 180-grain rounds flew at 952 fps and brought with them 362 ft.-lbs. of muzzle energy.
Our Team Said: When it comes to subcompact power, we think the G29 deserves more than just a serious look. 10mm was designed as an alternative to 45 ACP, and it provides similar if not more power. The difference was in the delivery — less torque, but a little more snap, quicker cycling, and a slightly smaller hole. Comparing typical bullet weights, the 180-grain 10mm rounds carry a little easier than 230-grain forty-fives. Otherwise, 10mm and 45 ACP guns typically weigh about the same. When compared to 40 S&W pistols, it took a radical load such as the Pow’R Ball to compete with standard 10mm numbers. Overall, the G29 more than proved its worth.
1011-NEW-POLYMER-ACC-CHRONO.pdf
1011-SPRINGFIELD-ARM-XDM-38-COMPACT.pdf
1011-GLOCK-G23-GENERATION-4.pdf
1011-PERSONAL-DEFENSE-ACC-CHRONO.pdf
I have a quick question will the G Flex work in a G29