Barrel Race 2017
A few months back we announced our plans to pitt as many Glock 17 barrels as we could get our hands on against each other in a head-to-head accuracy test. Why did we want to run this test? When describing a Glock’s accuracy the phrase “combat accurate” often comes up. We have certainly found this to be true. They are no slouch in the accuracy department, but they aren't quite what people would describe as “match grade” handguns. We have found that with good trigger control Glock’s can make easy torso hits at 50 yards. However the today's competitive sports sometimes demand hit out to 100 yards and on unforgiving targets in short timeframes. It’s no surprise that many shooters at the top of the competitive field have turned to platforms with multiple locking lugs, bushing fit bull barrels, and sliding triggers. Even in a defensive handgun where reliability is valued over raw precision. If you could get more accuracy. Wouldn’t you want to.
There are several options to improve the accuracy of a handgun system. The first and most critical step is to become a better shooter. Frankly most shooters don’t have the training or discipline to fully appreciate the accuracy of any handgun whose trigger weighs more than three pounds. Of course along with training you can increase the precision of your interaction with the gun by improving the trigger pull and installing sights that give you a better realization of you point of aim. Once you have taken these steps, especially the training part, you begin to get an idea of the inherent mechanical accuracy of the gun. The only other way to affect the accuracy is to replace the barrel. For years several makers of custom parts have offered “Match Grade” Glock barrels that promise to squeeze more precision out of the system by having tighter tolerances, presumably in the rifling and lockup areas. Recently the number of companies offering “drop in” barrels has increased significantly. This has been largely led by the increasing popularity of the action shooting sports and the recent public demand for threaded barrels on which to mount silencers.
Looking across the spectrum of barrel maker’s we took notice of the claims many of the manufacturer's assigned to their product. Exciting phrases were used such as “mathematical symmetry”, “critical tolerances” and “desirable machinability properties.” It all reads very fancy,, but what does any of it mean for you the consumer, and more importantly for your target. Interesting enough, only Wilson Combat submitted an actual group size claim stating that their barrel would shoot groups of “2 inches or Less At 25 Yards With Good Ammo.” Sending out a letter of intent, we corresponded with a total of 19 manufacturers, asking them to provide a barrel for testing purposes. In the end we received 9 aftermarket barrels along with a factory threaded barrel from Glock. These joined the stock barrel for a total of 11 contestants.
The test was performed using a brand new Gen 3 Glock 17. The handgun was fired from a Ransom Master Series Rest. When it comes to accuracy testing fixtures the industry standard is the Ransom Rest. Built like a vice, but with the precision of a lathe, the Ransom Rest uses three bolts and two metal plates to clamp the grip of a handgun in a model specific steel/polymer hybrid insert. When locked into the device, the handgun can be loaded and fired using a lever without the analyst having to contact any part of the gun. When fired the gun is able to recoil in an arc as it would in a human hand, but instead of a wrist it tilts backwards on a precisely machined hinge that guarantees a repeatable point of aim. Once mounted it is also possible to easily change barrels without removing the frame.
For these very reasons it is the primary test fixture used by the majority of firearms manufacturers. An alternative method to test a barrels accuracy is by locking the barrel into a device separate from the handgun, and firing it from the fixture. While this may give a picture of how precisely machined a barrels rifling is it doesn’t provide any account to the consistency of the rest of the barrel. Barrel accuracy is achieved through not only the rifling, but also the fit between the barrel and the slide and the barrels fit to the locking block. Using a Ransom Rest allowed us to test the performance of various barrels in the actual firearm they are designed to be used in, testing all aspects of the barrel rather than just the rifling.
To mount the Ransom Rest we had to create a stable and level mounting surface. Using 4x4s and a double layer of inch thick fiberboard we constructed a table that was sunk 3 feet into the ground. All 4 legs were cemented in place with a total of 200 pounds of Quikrete. The rest was then secured to this surface using four heavy duty industrial c clamps. This allowed us to create near identical testing procedures from barrel to barrel.
Wanting to obtain the most accurate results possible, we researched the testing procedures that reputable organizations conducting similar tests had used to obtain their results. Based upon this research we developed the following test procedure. We would fire five, five shot groups, with three different types of ammunition each, at 25 yards. After measuring the group size of each target we would calculate each barrels average group size for each of our three bullet weights as well as each barrels average overall group size. We wanted the test to represent the three most commonly used 9mm bullet weights. Fortunately three companies we reached out to came through big time and made the test possible by providing over a thousand rounds of ammunition. A local company Atlanta Arms provided us with their Elite Match 115 Grain JHP ammo. Precision Delta provided their 124 grain JHP Performance Pro ammo. Finally Freedom Munitions sent boxes of their ProMatch 147 Grain Hollow Points.
Be a gun blogger they said. It will be fun they said. Running this test gave me a much greater appreciation for those who work in the scientific side of the firearms industry. Pulling a lever 825 times for an entire afternoon while trying to apply the exact same amount of pressure each time is about as much fun as it sounds, but we got it done. Throughout 75 rounds a piece not one of the barrels failed to cycle a single time. After 5 hours of constant gunfire, stapling, mag stuffing, and target labelling we had the raw information. Now we just needed to process it. Following the firing day all 165 targets were scanned onto our computers. We then measured the group sizes using the TARAN (Target Analysis and Rifle Precision) software. As you can image, firing 825 rounds of 9mm through a gun you can’t even touch was quite tedious. Even worse was sitting down with a computer and tagging each individual bullet strike. Fortunately the TARANs intuitive interface greatly streamlined the process. Finally after hours of pizza fueled tagging and calculations our results began to emerge.
Enough drivel. You came for a chart. Here it is.
The overall winner was KKM with an average group size of 1.92 inches. The only barrel of the test to average under two inches. What we immediately noticed was the difference in performance with each brand of ammunition. The Precision Delta 124 Grain Performance Pro was the top performer at 2.375 inches. The Atlanta Arms Elite Match 115 Grain was a close second at 2.392 inches.
The Freedom Munitions ProMatch 147 Grain HPs came in third with an average group size of 3.424 inches. Many competitors choose the heavier bullets because they provide less recoil when loaded to meet required power factors. The results seem to show that this weight doesn’t provide as tight of a group as it’s lighter competitors. Of course, it's possible that the difference in ammunition performance has more to do with the projectiles consistency and means of manufacturing than its weight.
It is also worth noting that the Freedom Munitions projectile was plated, while the others were both jacketed. The barrel from Blacklist Industries was the best performer with the Freedom 147s. It shot an average group of 1.85 inches with a projectile the other barrels seemed to struggle with. While its averages with the lighter projectiles were both over 2 inches, it is worth noting how well it performed with 147 Grain ammunition. This would seem to be attributable to the differing twist rates of the barrels. KKM is spun at 1 in 20 inches and performed the best with the lightest 115 Grain projectiles Wilson which is spun at a rate of 1 in 16 inches performed best with the 124 Grain bullets. The Blacklist barrel is spun at a faster 1 in 10 inches. As our rifle savvy readers may expect this allowed it to throw the heavier 147 Grain projectiles with more accuracy. We were unable to get exact twist rate data for all three barrels, but it would seem that a few were spun to favor the heavier projectiles far better than those with a slower ( correct) twist.
This is definitely worth noting if you are a competitor looking to buy a match barrel for a specific load. Also consider that in the end what blasted KKM past the competition wasn’t just the fact that slung the 115 grains for a shocking average group of 1.61 inches, but the fact that its averaged so well with all of the projectiles.
Seeing these results we would hope that dedicated gamers looking to push their Glocks to their maximum competitive potential find useful data to help them make an educated purchase. However it hasn’t escaped my notice that sitting right in the middle of the pack with an extremely respectable 2.50 inch average is. . . Glock! Seeing this we would encourage new Glock owners, especially those looking for a fighting pistol not the be too quick to throw their factory tubes in the waste bin next to the plastic sights and 5 pound connector. Because it turns out it’s one hell of a barrel.
Though we set out on this journey to learn more about the performance of these barrels we think the biggest lesson we learned was the importance of quality ammunition. Before the actual test day in order to practice and troubleshoot our test procedure we ran several rounds of “Junk” 115 grain ammo through each barrel. It consisted of range trash from my trunk and several random boxes we found sitting outside in a golf cart at our testing location. While this ammunition certainly showed different levels of performance between the barrels it threw far larger groups than the match ammo. If we were looking to improve the mechanical accuracy of our handgun, we would first look to quality ammunition before making any modifications to the firearm.
Gathering these results was a lot of fun, but also a lot of work. We are glad that we were able to gather this information and hope it proves useful for any Glock owner focused on pursuing victory!