One aspect of farming that is conducive to acceptable crop harvests is managing the number of whitetail deer in your area. It provides a fun alternative to pursuing a mature buck and it puts meat in your freezer. Ample shot opportunities also allow me to try several different firearms and load combinations each season to learn their effectiveness, or lack thereof. Over the past decade, I’ve become a fan of long-range hunting rifles. Typically, these are stiff-barreled bolt actions. Lately, however, I’ve learned that a well-built self-loader can be as accurate as a custom bolt action. With this knowledge in mind, I set out to build a flat-shooting 6.5 Creedmoor on an AR-platform MATEN receiver set from Mega Arms.

Sturdy Foundation

My custom 6.5 Creedmoor began with Mega’s MKM KeyMod upper receiver and its matching ambidextrous lower. The receivers are milled from a solid billet of 7075-T6 aluminum with distinctive contours. The receivers and handguard feel quite sturdy, with their combined weight of 42 ounces disassembled. Of note, the MATEN upper and lower receivers accept a wide variety of .308 components. Included in this new platform are an upper receiver, a lower receiver, a billet charging handle, a threaded bolt catch pin, takedown pins, an ejection port cover and an upper receiver tensioning screw. When assembled, the upper and lower receivers lock up tight as a vault thanks to close manufacturing tolerances and the tensioning screw.

Mega’s billet upper and lower have been designed to be the most versatile and compatible platform available, which is evidenced by the wide variety of other manufacturers’ components that fit this receiver set. The MATEN comes standard with laser-engraved T-markings on the top Picatinny rail. An integrated triggerguard adds functionality and strength, and the included billet charging handle features an anti-slip surface for an improved grip.

More Details

As mentioned, the MATEN’s capabilities make it an AR builder’s dream. These receiver sets are designed to accept any AR-style .308 barrels and bolts, which means you can use your AR-10/Noveske or SR-25/DPMS components. Mega Arms recommends using the same manufacturer for your barrel and bolt, and the company suggests that “assembly should always be done by a qualified gunsmith, using the proper headspacing gauges.”

Aside from Mega Arms’ monolithic upper receiver, the company offers the two-piece MML (Mega M-LOK) and MKM uppers, the latter of which I used for my build. Both are machined to accept Mega’s lightweight aluminum handguards. These handguard attach to the upper receiver via an octagonal male/female orientation. Once the upper and handguard are assembled, 12 screws tightly attach the two units rigidly together.

Building It Up

My parts list for the MATEN build leaned heavily toward components from JP Enterprises, including a JPE Supermatch barrel chambered in 6.5 Creedmoor. The medium-contour, 416R stainless barrel measures 22 inches long and features a 1-in-8-inch twist rate as well as 5/8×24 threading. This premium barrel is lead lapped, air gauged and cryogenically treated for excellent accuracy, minimal thermal drift and extended longevity. An EnhancedBolt individually headspaced to the barrel from JP Enterprises was also included.

The first step in installing the barrel is to apply a thin coat of lithium grease on the barrel where it slides into the Mega Arms upper receiver, carefully assuring that the barrel’s alignment pin indexes into the receiver’s alignment slot. More lithium grease was applied to the MATEN’s barrel nut to keep it from galling when torqued down. I attached the supplied Mega Arms barrel nut wrench to a 0.5-inch torque wrench and set it to 65 foot-pounds of torque.

The next step in the assembly was to install the gas block and center it with the supplied marking screw. This left a faint mark on the barrel as an index point. I placed the barrel in a vise block and used a drill press to drill a slight dimple. When the gas block was replaced, the final setscrew was used to help lock the part in place on the barrel. The rifle-length gas system is managed with a JPE JPGS-8 low-profile adjustable gas block. I also installed a blue JPE Thermal Dissipator to match my taste. Next I installed the MATEN handguard and added a short KeyMod rail on the bottom to accommodate a bipod.

Next Steps

In keeping with the other JPE parts, I selected an LMOS (Low-Mass Operating System) bolt carrier group and a Silent Captured Spring. JPE’s LMOS is a departure from .308 AR-type bolt carrier assemblies. It weighs only 14.7 ounces, and counteracting the lighter bolt assembly is a heavier recoil spring in the Silent Captured Spring. The benefit of the spring set is that it eliminates the characteristic “twang” when you pull the trigger.

Next on the agenda was a stock. I installed a mil-spec, rifle-length receiver extension and attached a Magpul PRS stock to it. This stock is designed for the longer charging handle throw of .308 platforms. The PRS is adjustable for both comb height and length of pull via machined-aluminum adjustable knobs with positive-locking click detents. The stock also offers a bottom rail for a monopod, and I attached an Accu-Shot monopod to match the Atlas bipod up front for shooting stability.

The supplied single-stage Mega Tactical Trigger offers adjustments to minimize overtravel and trigger creep. It features a wide leading edge for comfort and aesthetics. My test sample broke cleanly at 4.5 pounds.

Range Setup

At the range, I tested the rifle with and without an Advanced Armament Corporation (AAC) Cyclone suppressor. A proper optic was only befitting, so I mounted a Trijicon AccuPoint 5-20x50mm scope with a mil-dot reticle. Previous experience with high-ballistic-coefficient bullets and the velocity this rig was capable of producing led me to believe that I could use the mil dots as aiming points that closely corresponded with 100-yard increments.

To put the 6.5 Creedmoor build through its paces, I selected one factory load and did some experimenting with several handloads. Velocity data was collected with an Oehler 35P chronograph. I loaded up a Magpul 20-round magazine and got started. By the way, Mega Arms’ receivers are compatible with any SR-25/DPMS-type magazine, such as those from Magpul Industries, Knight’s Armament, CMMG and C Products.

Hot Shots

The first load I tested was a 123-grain Hornady A-MAX driven by 38 grains of Reloader 15. I knew right away that this wasn’t going to be this rifle’s pet load, since the five-shot groups measured about 1.5 inches at 100 yards. The best group measured 1.24 inches. Things got decidedly better when I switched to a 110-grain Speer hollow point driven by 41 grains of Varget. This load produced a best five-shot group of 0.48 inches. The next load, featuring a 123-grain Sierra MatchKing and 39.2 grains of Varget, produced a 0.34-inch group.

I moved up in weight to a 140-grain Berger VLD driven by 42.8 grains of W760, which averaged 2,662 fps. With this combination, the smallest group measured 1.09 inches. The same powder charge driving a 140-grain A-MAX produced a 0.57-inch group. Off to a good start, I feel that this custom 6.5 Creedmoor rifle is capable of 0.25-MOA groups with a little more fine-tuning.

In The Field

The range work completed, it was time to put the new rifle through its paces on a late-season deer hunt. My stand site was familiar; I simply set up on my range bench and waited. A 760-yard strip of rye, Mossy Oak BioLogic and other assorted Mossy Oak beets, bulbs, chickory and clover run along the length of my range. Several 1.5- and 2.5-year-old bucks had received a pass throughout the season, but it was time to continue my work of controlling the doe population. After a short wait, I had a skinny one-horned spike step into my “food plot” at 30 yards. Within a few seconds, a young six-pointer followed. Neither of these bucks was in danger because of their age.

As the sun dropped toward the horizon, a doe fawn stepped into view downrange and looked back over her shoulder. I raised my Leica 1600-B CRF rangefinder and plated the red box squarely on the young doe’s side. The readout told me that she stood 522 yards away. A few moments later, a mature doe stepped into the lane and quickly crossed out of view.

Her caution eased, the big doe stepped back into view 10 yards closer. I twisted the Accu-Pod slightly and settled the third mil dot just above the doe’s midline, right behind her shoulder, as she stood broadside feeding. The trigger broke crisply, launching the 123-grain A-MAX with a suppressed crack of a suppressed hypersonic round leaving the barrel. My spotter, my wife Jacqueline, watched through 10X Kowa binoculars as the bullet struck home. The doe bucked her back feet, ran a few steps and tipped over.

Final Thoughts

Successful at long range on its first hunt, this custom 6.5 Creedmoor rifle is guaranteed to accompany me to the range and field until the round count gets so high that I wear the barrel out. Then, I’ll just tear it down, replace the barrel and put this rugged rifle back into service for a few more years.

Custom 6.5 Creedmoor Rifle Specs

Caliber: 6.5 Creedmoor
Barrel: 22 inches
OA Length: 41.88 inches
Weight: 10 pounds (empty)
Stock: Magpul PRS
Sights: None
Action: Direct impingement semi-auto
Finish: Matte black
Capacity: 20+1

Custom 6.5 Creedmoor Rifle Performance

Handload Powder Velocity Accuracy
Berger 140 VLD 42.8 W760 2,662 1.09
Hornady 1123 A-MAX 38 Reloader 15 2,641 1.24
Sierra 123 MatchKing 39.2 Varget 2,710 0.34
Hornady 140 A-MAX 42.8 W760 2,673 0.57
Speer 100 HP 41 Varget 2,894 0.48

*Bullet weight measured in grains, velocity in fps by chronograph and accuracy in inches for best 5-shot groups at 100 yards.

For More Information

JP Enterprises


Mega Arms

This article was originally published in “AR Rifleman” 2016. To subscribe, visit

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