Molon

Criterion 16” CORE Barrel Accuracy Evaluation Well over a decade ago, the late John Noveske was the impetus for bringing modern AR-15 barrel profiles to the civilian market. His 16" CHF N4 barrel profile has the same weight as a government profile barrel of the same length, but it has a more intelligently designed contour that places more of the weight of the barrel from the chamber to the gas block journal and does away with the M203 cut-outs. Over the last several years we’ve seen the emergence of barrels produced by multiple manufacturers with the specific objectives of balancing weight distribution, heat absorption and handling characteristics while at the same time endeavoring to improve upon the accuracy/precision of old school barrel profiles of similar weight. Criterion Barrels CORE series of barrels is a prime example of this modern approach to profiles for AR-15 barrels. The Criterion 16” CORE barrel reviewed for this article has a stripped weight of exactly 1 pound, 12.0 ounces. This is the same weight as a Colt 16” government profile barrel. As with the Noveske CHF N4 barrel, the CORE barrel profile has done away with the useless M203 cutouts. More of the barrel material has been shifted to the aft of the barrel for a “continuous taper” profile. The gas block journal for the CORE barrel is 0.625”. The 16” CORE barrel . . . The barrel stamp reads: CRITERION 223 WYLDE 1-8 The date code on this barrel reads: 08/21. The CORE barrel is button-rifled and the bore is hand-lapped. The bore and chamber are chrome-lined. As pictured above, the barrel has a 223 Wylde chamber, a 1:8” twist and utilizes a mid-length gas system. The gas port diameter gauged at 0.078”. For comparison, a larue 16" predatar barrel has a gas port diameter of 0.082". The gas block journal of the CORE barrel has a single dimple contralateral to the gas port. The barrel extension has M4 feed-ramps, although it is not marked as such like a Colt barrel extension. The crown. I installed the Criterion 16” CORE barrel in a new Colt cage-code M4 upper receiver and free-floated the barrel with a Geissele MK16 rail. A new JP Enterprises EnhancedBolt closed on a 1.4646” headspace gauge and did not close on a 1.4666” headspace gauge. I conducted an accuracy (technically, precision) evaluation of the Criterion 16” CORE barrel from my bench-rest set-up following my usual protocol. This accuracy evaluation used statistically significant shot-group sizes and every single shot in a fired group was included in the measurements. There was absolutely no use of any group reduction techniques (e.g. fliers, target movement, Butterfly Shots). The shooting set-up will be described in detail below. As many of the significant variables as was practicable were controlled for. Pictures of shot-groups are posted for documentation. All shooting was conducted from a concrete bench-rest from a distance of 100 yards (confirmed with a laser rangefinder.) The free-float hand-guard of the rifle rested in a Sinclair Windage Benchrest, while the stock of the rifle rested in a Protektor bunny-ear rear bag. Sighting was accomplished via a Leupold VARI-X III set at 25X magnification and adjusted to be parallax-free at 100 yards. A mirage shade was used. Wind conditions on the shooting range were continuously monitored using a Wind Probe. The set-up was very similar to that pictured below. The Wind Probe . . . The accuracy evaluation of this barrel began with factory loaded Federal 77 grain Gold Medal Match ammunition. One of the first groups fired from this barrel had an extreme spread of 0.18”. That group is pictured below. The very next group fired from this barrel had an extreme spread of 1.5”. That 10-shot group is pictured below. A 10-shot group with an extreme spread of 1.5” is perfectly acceptable for a 16” chrome-lined AR-15 barrel with a weight of 1 pound, 12 ounces. However, this barrel isn’t broken-in yet. The bore-scope image shown below was taken prior to any shots being fired. It shows the sharp tooling marks on the lands in the leade, which run perpendicular to the direction of bullet travel. For the barrel to shoot to it’s potential, the sharp edges of these tool marks need to be “burnished” out. So, I continued shooting 10-shot groups using a variety of factory loads and hand-loads. For comparison, the bore scope view shown below is from the leade of a Colt M4A1 SOCOM barrel that's been fully broken-in. As the fired round-count for the CORE barrel approached 150, the size of the groups shrank and became more consistent. At this point, I fired the three 10-shot groups “of record” using one of my standard match-grade hand-loads topped with Sierra 55 grain BlitzKings. When fired from my Krieger barreled AR-15s, this load has produced ½ MOA 10-shot groups at 100 yards. The three, 10-shot groups fired in a row from the Criterion 16” CORE barrel from a distance of 100 yards had the following extreme spreads: 1.15” 1.09” 1.13” for an average 10-shot group extreme spread of 1.12”. The three, 10-shot groups were over-layed on each other using RSI Shooting Lab to form a 30-shot composite group. The mean radius of the 30-shot composite group was 0.39”. The smallest 10-shot group . . . The 30-shot composite group . . . ....

I do, however, think that the "average" M&P9 4.25" or 5" is probably not as accurate as the "average" SIG, Glock, HK, etc. Aggreed. SIG P226 Stainless with factory barrel . . . H&K VP9 with factory barrel . . . Glock 19 with factory barrel . . . M&P9 PRO CORE with factory barrel . . . M&P9 PRO CORE with APEX barrel . . . .....

The "single dimple" barrels also have the 1:10" twist. There was no significant difference in the accuracy between the single dimple and double dimple barrels that I tested. ...

06/10/16 To date, I have a total of 1105 rounds fired through the Apex barrel; no malfunctions to report. Velocity Comparison I compared the velocities of three different bullet weights fired from the Apex Grade barrel fired back-to-back with the factory original barrel. The strings of fired consisted of 10-shots over an Oehler 35-P chronograph. All velocities listed in the table below are muzzle velocities, as calculated from the instrumental velocities using Oehler's Ballistic Explorer software. Atmospheric conditions Temperature: 78 degrees F Humidity: 42% Barometric pressure: 30.03 inches of Hg Elevation: 950 feet above sea level ....

..... 05/07/16 Here's a pic of another 10-shot group fired off the the bench at a distance of 25 yards. This group was fired using one of my standard hand-loads (not tuned for any particular barrel) that is seated with the Federal 124 grain HST bullet. The group has an extreme spread of 1.08". Strictly for kicks and giggles, here's a pic of a statistically insignificant 5-shot group fired from the bench at a distance of 25 yards. The group has an extreme spread of 0.75". ..... 5/08/16 To date, I’ve fired 850 rounds from the Apex barrel. There have been no malfunctions to report. .... As before, the statistically insignificant 5-shot groups pictured below are strictly for kicks and giggles. These groups were fired off the bench at a distance of 50 yards. This group was fired using Federal factory loaded 147 grain HST ammunition. The group has an extreme spread of 1.88” This next group was fired using one of my standard hand-loads (not tuned for any particular barrel) that is seated with the Speer 124 Gold Dot bullet. The group has an extreme spread of 1.49” Continuing with one of my standard hand-loads topped with the Hornady 90 grain XTP bullet, the Apex barrel turned in this 5-shot group with an extreme spread of 1.38”. Lastly, my particular barrel has shown a preference for the 124 grain HST projectile. This 5-shot group was fired using my standard hand-load for that bullet. The group has an extreme spread of 0.93”. ....

02/28/16 To date, I’ve fired 150 rounds of quality factory loaded ammunition through the Apex Grade Gunsmith Fit Barrel during function testing and barrel break-in. I like to have fired at least 200 rounds through a pistol barrel before conducting an accuracy evaluation of it. There have been no malfunctions with the Apex barrel in my M&P9 CORE while firing an assortment of: Federal 9BP 115 grain JHP Speer 124 grain Gold Dot Federal 9MS 147 grain JHP Federal 147 grain HST Speer 147 grain Gold Dot G2. Since the Apex Tactical Specialties test-target was fired at a distance of only 10 yards, I did fire a few 10-shot groups from a distance of 10 yards (from the bench) for comparison. The group pictured below was fired using factory loaded Federal 147 grain HST ammunition. The group has an extreme spread of 0.633”. .... .... 03/08/16 The 10-shot group pictured below was fired at a distance of 15 yards using factory loaded 124 grain Gold Dot ammunition. The group has an extreme spread of 0.912". ..... 03/12/16 At this point, I have a total of 300 rounds of factory-loaded ammunition fired from the Apex Grade Gunsmith Fit Barrel and have not had any malfunctions. The 10-shot group pictured below was fired from the bench at a distance of 25 yards using factory-loaded Federal 124 grain HST ammunition. The group has an extreme spread of 1.38" .... The recessed crown . . . .....

Apex Grade Gunsmith Fit Barrel - 4.25” I purchased my Apex Grade Gunsmith Fit Barrel (4.25”) directly from Apex Tactical Specialties. I shipped my Smith & Wesson M&P9 CORE directly to them for the fitting/installation of the barrel. The pics shown below give you a look at the different geometry that Apex Tactical Specialties developed for their barrel. I paid the additional fee for Apex Tactical Specialties to test-fire my M&P9 CORE after their fitted barrel was installed. The test-target that was included with my returned pistol is pictured below. Aside from some brief demographics written on the test-target, the only technical information that was written on the test-target was a note stating: 10 @ 10 I can only assume that meant that the test-target was of a 10-shot group fired at a distance of 10 yards. The group has an extreme spread of 2.226”. An extreme spread of 2.226” at 10 yards would sub-tend to an extreme spread of 5.565” at 25 yards. My M&P9 CORE grouped better than that with the original factory barrel. The Apex Tactical Specialties test-target . . . In a duplicate of this thread that I posted on another website, Randy Lee (co-owner of Apex Tactical Specialties) posted the following comments about the test-target. “I figured I should chime in about the test target in question. The target does reflect 10 shots from a distance of 10 yards offhand. It was what our technician shot for function and approximate sight in after the barrel was fitted, not for group. The technician was shooting in a poorly lit indoor range using the iron sights, since the optic was not provided. This was also in the mix of some 20 firearms that the tech had to test fire that day. While I will not make any excuses for the large group, it is important to bear in mind that the gun is obviously capable of consistent mechanical accuracy. The test fire fee is not the same as the Ransom Rest accuracy charge. If you were charged for the Ransom Rest test, please call our office so we can arrange for your gun to be returned to us for expedited Ransom testing. We differentiate function/sight adjustment targets from accuracy targets by the red center. When I shoot from the Ransom Rest, I use a black and white target with a black dot in the center because the RMR dot matches the 1" black center at 25 yards. . . . We are changing our test fire procedures for barrels we fit in house as a result of this thread to reflect mechanical accuracy. It was one of the things that slipped through the cracks since I have been doing more administrative work that back at the bench or in the shop.” ...

05/08/16 To date, I’ve fired 850 rounds from the Apex barrel. There have been no malfunctions to report. .... As before, the statistically insignificant 5-shot groups pictured below are strictly for kicks and giggles. These groups were fired off the bench at a distance of 50 yards. This group was fired using Federal factory loaded 147 grain HST ammunition. The group has an extreme spread of 1.88” This next group was fired using one of my standard hand-loads (not tuned for any particular barrel) that is seated with the Speer 124 Gold Dot bullet. The group has an extreme spread of 1.49” Continuing with one of my standard hand-loads topped with the Hornady 90 grain XTP bullet, the Apex barrel turned in this 5-shot group with an extreme spread of 1.38”. Lastly, my particular barrel has shown a preference for the 124 grain HST projectile. This 5-shot group was fired using my standard hand-load for that bullet. The group has an extreme spread of 0.93”. ....

Yes. Every Barrel Is A Law Unto Itself ...

05/07/16 Here's a pic of another 10-shot group fired off the the bench at a distance of 25 yards. This group was fired using one of my standard hand-loads (not tuned for any particular barrel) that is seated with the Federal 124 grain HST bullet. The group has an extreme spread of 1.08". ...

The Hogue rubber grips are nice, but they feel larger than the standard grips. As others have mentioned, the G10 grips are a fine choice. I'm also partial to Nill Grips. ....

My VP9 has a shown a preference for 124-125 grain bullets. The Hornady 124 grain FMJ-FP seated long and loaded to a PF of 130 produced a 10-shot group at a distance of 25 yards that had an extreme spread of 1.87". Stepping up the PF to 137 and using the Hornady 125 grain HAP, also seated long, my VP9 turned in a 10-shot group at 25 yards that had an extreme spread of 1.6". ...

I'm more interested in how long it took to put together that post complete with precisely measured and documented photos! Kudos... makes my posts look like they were slapped together half-assed (which they were). I agree. A very nice post. Thanks. Here are a few more pics of the barrel. .....

IIRC it was approximately seven weeks. ...

Apex Grade Gunsmith Fit Barrel - 4.25” I purchased my Apex Grade Gunsmith Fit Barrel (4.25”) directly from Apex Tactical Specialties. I shipped my Smith & Wesson M&P9 CORE directly to them for the fitting/installation of the barrel. I paid the additional fee for Apex Tactical Specialties to test-fire my M&P9 CORE after their fitted barrel was installed. The test-target that was included with my returned pistol is pictured below. Aside from some brief demographics written on the test-target, the only technical information that was written on the test-target was a note stating: 10 @ 10 I can only assume that meant that the test-target was of a 10-shot group fired at a distance of 10 yards. The group has an extreme spread of 2.226”. An extreme spread of 2.226” at 10 yards would sub-tend to an extreme spread of 5.565” at 25 yards. My M&P9 CORE grouped better than that with the original factory barrel. The Apex Tactical Specialties test-target . . . In a duplicate of this thread that I posted on another website, Randy Lee posted the following comments about the test-target. “I figured I should chime in about the test target in question. The target does reflect 10 shots from a distance of 10 yards offhand. It was what our technician shot for function and approximate sight in after the barrel was fitted, not for group. The technician was shooting in a poorly lit indoor range using the iron sights, since the optic was not provided. This was also in the mix of some 20 firearms that the tech had to test fire that day. While I will not make any excuses for the large group, it is important to bear in mind that the gun is obviously capable of consistent mechanical accuracy. The test fire fee is not the same as the Ransom Rest accuracy charge. If you were charged for the Ransom Rest test, please call our office so we can arrange for your gun to be returned to us for expedited Ransom testing. We differentiate function/sight adjustment targets from accuracy targets by the red center. When I shoot from the Ransom Rest, I use a black and white target with a black dot in the center because the RMR dot matches the 1" black center at 25 yards. . . . We are changing our test fire procedures for barrels we fit in house as a result of this thread to reflect mechanical accuracy. It was one of the things that slipped through the cracks since I have been doing more administrative work that back at the bench or in the shop.” .... 02/28/16 To date, I’ve fired 150 rounds of quality factory loaded ammunition through the Apex Grade Gunsmith Fit Barrel during function testing and barrel break-in. I like to have fired at least 200 rounds through a pistol barrel before conducting an accuracy evaluation of it. There have been no malfunctions with the Apex barrel in my M&P9 CORE while firing an assortment of: Federal 9BP 115 grain JHP Speer 124 grain Gold Dot Federal 9MS 147 grain JHP Federal 147 grain HST Speer 147 grain Gold Dot G2. Since the Apex Tactical Specialties test-target was fired at a distance of only 10 yards, I did fire a few 10-shot groups from a distance of 10 yards (from the bench) for comparison. The group pictured below was fired using factory loaded Federal 147 grain HST ammunition. The group has an extreme spread of 0.633”. .... 03/08/16 The 10-shot group pictured below was fired at a distance of 15 yards using factory loaded 124 grain Gold Dot ammunition. The group has an extreme spread of 0.912". ..... 03/12/16 At this point, I have a total of 300 rounds of factory-loaded ammunition fired from the Apex Grade Gunsmith Fit Barrel and have not had any malfunctions. The 10-shot group pictured below was fired from the bench at a distance of 25 yards using factory-loaded Federal 124 grain HST ammunition. The group has an extreme spread of 1.38" ..... 4/17/2016 Strictly for kicks and giggles, here's a pic of a statistically insignificant 5-shot group fired from the bench at a distance of 25 yards. The group has an extreme spread of 0.75". ....