6.8 SPC AR-15 Carbines: The Stag Arms 5L Gets the Nod
Shooting the stout midrange cartridge, the heavily-tricked-out Stag outdueled carbines from DPMS and Rock River, both of which had feeding problems that made them into single-shots.
The AR-15 platform is booming not only in total unit sales but also in aftermarket accessories such as buttstocks, hand guards, sights, you name it. Perhaps even more significant is the availability of ARs chambered for calibers other than .223 Remington—the greatest indication that shooters like something is that they’re willing to tinker with it.
In this test we will evaluate three such carbines with 16-inch barrels chambered for 6.8mm SPC ammunition. All three of these models were flat-top designs featuring a Picatinny rail atop the receiver. They were the $1114 DPMS AP4 Panther Carbine that came with a $124 JP Enterprises trigger upgrade; the $925 RRA LAR-6.8 Mid-Length A4 from Rock River Arms, and a left hand (left-side ejection) 5L from Stag Arms. The base price of a Stag Arms 5L was $1095, but our Stag was customized with several options that added nearly $1000 to the retail list price.
Would these features give the Stag an unfair advantage when compared to the Rock River and DPMS products? We think the answer is no, and here is why. Given the modular design of the basic platform, every feature found on the customized Stag 5L could also be applied to our other test samples as well as any other AR, carbine or rifle. Therefore, we felt that we would be able to isolate the benefit of a given modification and render judgment on the basic weapon. For example, if the compensator on the Stag were to help us get better hits, we still might prefer one of the other carbines but recommend the application of said compensator.
The 6.8 SPC presents a bullet that is about 0.27 inches in diameter typically weighing 110 to 115 grains. The difference in overall cartridge size between 6.8 SPC and .223 Remington ammunition does not appear to be major. But 6.8 SPC magazines of the same length as 30-round .223 magazines hold five rounds fewer. Our test ammunition was Remington’s 115-grain Express Rifle OTM and two rounds from Hornady Manufacturing. They were the 110-grain V-Max Varmint Express and 115-grain BTHP/WC Custom loads.
Our first encounter with a 6.8 SPC carbine was reported in the November 2008 issue of Gun Tests. This was Ruger’s handy Mini 14. Now we had a chance to see if this caliber was better suited to the AR-15. We began our tests by mounting a Nikon Monarch 2-8X32mm BDC scope No. 8438. This was a 1-inch-tube scope with four circles below the crosshairs for instant holdover. We liked the Monarch’s range of power and its clear field of vision. We could have chosen this same model with the Nikoplex reticle instead of the BDC circles for $10 less, (catalog number 8437), but we were curious to see if the reticle really worked. We mounted the scope utilizing a Yankee Hill Machine scope riser and a pair of B-Square Tactical Tri-rings ($74 from brownells.com). We think the addition of Nikon target turrets enhanced function as well as visual appeal. For collecting accuracy data from the 100-yard line we traveled west from downtown Houston to American Shooting Centers located in George Bush Park (amshootcenters.com). Our first step was to zero each carbine at the 50-yard bench. We blended in a break-in regimen of cleaning the barrel every five shots for the first 25 rounds. A fouling shot was fired after each cleaning. Then we moved to the 100-yard line to readjust our point of impact and record the width of five-shot groups, measuring the holes widest apart from center to center. We also planned a 200-yard firing session utilizing the first holdover circle and a rapid-fire test. Here is what we learned.