Review: Rock River Arms X-Series LAR-6.8 AR-15

posted on February 7, 2018

Whenever you garner the opportunity to shoot a new-to-you chambering, there’s always a mixture of anticipation and trepidation. How it will handle, whether it will kick like a mule or behave against your shoulder, if it will be easy to make repeated hits on target; all of these big question marks remain unanswered until you get to the firing line. One way to minimize the unknowns, of course, is to have a familiar platform. In the case of the Rock River Arms X-Series LAR-6.8, the 6.8 Rem. SPC cartridge is paired with the quite-familiar AR-15 platform. The rifle feels like every other rifle based on the AR-15 rifle I’ve ever handled, which shortened the time it took to get acquainted with the new round.

The “Hunter” muzzle brake made follow-up shots fast and painless.

Rock River Arms
introduced its X-Series at the NRA’s 143rd Annual Meetings & Exhibits in April 2015, with standard .223 Rem. and .308 Win. offerings as well as the less-traditional .458 SOCOM and, of course, the 6.8 Rem. SPC. All rifles come with a proprietary stock, two-stage trigger and a free-float, extended handguard topped with a Picatinny top rail containing attachment points for additional rail sections (at the 6-o’clock position). Different configurations are based on the stock (fixed or adjustable) and color (black or tan).

Rock River Arms’ Operator CAR stock provides six positions, making it simple to fit to an individual shooter.

This Rock River Arms X-Series LAR-6.8 was equipped with the adjustable-stock version in tan and fit with the “Hunter” muzzle brake. A 15-round magazine was provided, and given the number of discrepancies faced with loading the rifle, it would have been beneficial to have a second magazine to check whether the problems I encountered stemmed from the magazine or the rifle itself. Certain types of ammunition had considerable difficulties chambering, and several instances where the bolt failed to lock back on the empty magazine were noted.

The excellent, Rock River Arms-made, two-stage trigger is covered by the company’s “winter” trigger guard, which allows for access even when wearing thick gloves.

Accuracy, while still very good, did not reach Rock River Arms’ sub-MOA claim. A less-skilled trigger finger or employing an improvised rest may have contributed to this discrepancy. Overall, I saw the best performance using Hornady ammunition, resulting in 1.5-MOA accuracy at 100 yards. It’s absolutely sufficient for ringing steel in a competitive environment or taking an animal in the field, the latter being one of the tasks the 6.8 Rem. SPC was designed to improve versus the .223 Rem. Between the Rock River Arms X-Series LAR-6.8’s weight and the ability to configure it specifically to my profile, the extra recoil of the 6.8 Rem. SPC was not much harsher than the .223 Rem. I brought along on this range excursion.

A full-length Picatinny rail graces the top of the free-float fore-end, providing plenty of room for optics and accessories.

Despite the Rock River Arms X-Series LAR-6.8’s heft (it’s slightly heavier than the Smith & Wesson M&P10), it handled very well in informal testing. The testing range had several reactive targets (bowling pins) near the berm, so a quick test of the rifle’s handling was performed: A half-dozen pins were knocked down with a single hit each, in rapid succession, with the remaining rounds in the magazine used to send the downed targets skittering around the range. This was repeated numerous times, and while I didn’t have a timer handy, I found it extremely easy to drive the LAR-6.8 from pin to pin quickly. The rifle proved equally nimble during a similar test conducted at the same distance on an indoor range with paper targets. 

As mentioned previously, numerous failures to load were experienced, particularly with 85-grain frangible rounds. The Hornady 110-grain rounds had one failure to chamber as well as a single failure to lock the bolt on an empty magazine. The 115-grain Remington ammunition functioned flawlessly, which is to be expected as Remington developed the specialized cartridge. No failures to fire or eject spent casings were observed in the course of testing, with nearly 200 rounds fired.

For the experienced rifleman looking for a step up in potency from the .223 Rem., but who doesn’t need the full power of the .308 Win., the 6.8 Rem. SPC offers much promise. Rock River Arms’ superlative X-Series of rifles yields a dedicated platform for this round, one that is immediately familiar to aficionados of the AR-15-style rifle, helping ease acceptance of the cartridge among hunters and competitive shooters. For those looking for a little more power than the 5.56 NATO offers, in a familiar platform, the Rock River Arms X-Series LAR-6.8 is an attractive choice.


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