Rock River Arms LAR-9 Pistol Caliber Competition Carbine

Photos by: Oleg Volk and Gail Pepin

PCCs are niche firearms . . . and they fit more niches than ever. This one fits especially nicely.

 The pistol caliber carbine (PCC) has been around since the immediate post-Civil War era. “Back in the day,” they were chambered for rounds like .44 rimfire and .44-40; today, the most popular caliber (except for cowboy action shooting) is 9mm. For this issue, we test one such AR-15 platform: the LAR-9 from Rock River Arms, a brand highly respected among serious shooters. Ours is the competition carbine variation.

First Impressions

Weighing just under seven and a half pounds, the test gun came with a barrel fluted in chain link pattern, to lighten weight and give lots of cooling surface, and surrounded by an extended mid-length handguard. At the other end we find Rock River Arms’ Operator CAR telescoping stock. With the stock fully contracted, the overall length of this 16” barrel carbine is three and a quarter inches shorter than a yardstick.

The rifle’s bolt operates via blowback, doing away with the need for a gas block and tube, and saving even more weight on the frontend. RRA’s excellent Two-Stage Match trigger, oversized Winter Trigger Guard, non-binding Star Safety Selector and Hogue overmolded rubber grip are all standard equipment.

The magazine closely resembles that of an UZI, but is not interchangeable. The trigger guard is the popular bowed-downward style, allowing for deep-cold use with thick gloved fingers. The Picatinny top rail runs full length, from rear of receiver to front of handguard. Sights, including backup irons, are the user’s responsibility. The crew at home base at On Target had mounted a Vortex red dot optic and Magpul MBUS Pro flip-up sights before the rifle got to me.

Build quality was what we’ve come to expect from Rock River: top notch. Solid.

Shooting the LAR-9

The first thing all of us on the test team noticed was the fast, feather-light handling afforded by the light barrel. The weight felt centered more toward the firing hand, allowing the LAR-9 to track just lightning-fast between multiple targets, a handling feature that should translate equally well to moving targets.

The reasonably-priced and durable 2-MOA Vortex ( SPARC AR red-dot sight was used throughout testing. A truncated ejection port cover and large polymer case deflector and lack of a forward assist are deviations from the LAR-9s 5.56mm counterparts, but the location/size of the magazine-release button does not.

Another big advantage of that light front end comes in “wounded defender” shooting. That rearward balance point makes it easier to run this gun one-handed from the shoulder, and still get hits.

Measured with a Lyman digital gauge, the trigger pull ran 4.40 pounds average at the center, where the shooter’s trigger finger normally comes to rest. The toe, or bottom tip of the trigger, is farther away from the pivot point and thus gives more leverage to the entity pressing it back. In this case, pull weight was 3.87 pounds at the toe. That is more significant with a firearm like this than usual, because that bowed winter trigger guard actually allows the human index finger to comfortably get that low on the trigger.

The trigger assembly is Rock River’s own two-stage unit. RRA’s triggers have made a lot of friends among shooters, and this specimen was no exception: the movement of the trigger was always smooth, and the release of the sear always crisp.

The berm at the 100-yard line where my Caldwell Stable Table is set up was closed temporarily for reconstruction, and my new Caldwell rest designed for AR-15s and similar rifles didn’t arrive until the test gun had been packed up for return. Thus, accuracy testing was done from an impromptu bench rest on my 25-yard pistol range. This distance obviously isn’t the litmus test for a high-powered rifle, but remember, we were using a pistol caliber carbine here.

You won’t be inserting 5.56mm or .300 Blackout magazines into your LAR-9 by accident; note the solid-aluminum, 9mm-sized magwell in place of a downsized magwell insert. The LAR-9 feeds from a modified 32-round steel UZI magazine.

Many shooters feel that the operative term in “pistol caliber carbine” is actually “pistol.” Partly because it fires a pistol round, of course, but partly also because of Clint Smith. Clint was the one who really established the discipline he called Urban Rifle training in America, and one definition was the use of a rifle at what had heretofore been seen as “pistol fighting distance.”

As usual, each 5-shot group was measured twice, once for all five and once again for best three, the latter measurement generally balancing enough unnoticed human error to give about the same group size as the same gun and ammo would be expected to deliver for all five rounds from a machine rest. Measurements were taken center to center between the farthest flung bullet holes, to the nearest 0.05”. The three most popular bullet weights for the caliber were tested.


Remington 147-grain Golden Saber brass-jacketed hollow points yielded a 2.75″ 5-shot group, with four of those in 1.20″ and the best three in 0.85″. At the other end of the most popular 9mm bullet weight scale was American Eagle 115-grain full metal jacket. The American Eagle put all five shots in less than an inch, 0.95″ to be specific. Four of those five were under two thirds of an inch center to center, 0.65″. The best three were barely over half an inch apart, at 0.55″. For a middle-weight 9mm ammo (which would have been the heaviest available on gun store shelves 30 years ago), the choice was 124-grain Aguila full metal jacket. This load gave us a spot-on 1.00″ group with all five shots. Four were in the same 0.65″ as we found with the American Eagle, and the best three were a mere 0.45″ center to center.

Rock River’s jagged 9mm Mini Muzzle Brake not only does its job of mitigating muzzle rise, it also gives non-ballistic self-defense option in a close quarters fight. The cryogenically-treated, 16-inch stainless-steel barrel recieves a unique “chain link” fluting which serves to lighten the front end even further.

Rock River Arms advertises this model as capable of 1.5” groups at 50 yards. When we got groups like these using a red dot sight without magnification, extrapolating that at twice our 25-yard distance the group size should double (not counting wind, mirage, or other external factors) we felt Rock River had not been exaggerating with that 1.5”/50 yard promise.

Recoil was mild. The multiple shooters on the test team, ranging from big six-foot guys to one petite female, all felt the “kick” was indistinguishable from that of a .223 the same size and configuration. Everyone loved both the trigger, and the very ergonomic selector switch.

Reliability? We had a single malfunction, but it was a beaut . . . and it was my fault. I had noticed the gun was dry when it came out of the box, and was perversely curious to see how it would work that way, given the well-known truism that AR-15s need to be well lubricated. I found out. A couple hundred rounds into the test, I experienced an ejection failure that left a spent casing wedged transversely over the rear of a live 9mm cartridge that hadn’t made it all the way into the chamber. That was no “tap-rack” situation, and in serious use would have required immediate transition to the sidearm. I had to use a screwdriver to clear the stoppage. I then applied proper lube, and the Rock River 9mm ran fine for the rest of the test. The moral of the story? Do not run an AR-15 dry . . . do not eat the yellow snow . . . these are The Laws.

So, What’s It FOR?

The LAR-9 Competion is available with either M-LOK or Key-Mod compatible forends—our test rifle being the former. Slim and lightweight, being rifle-length is leaves plenty of real estate for a more-forward support hand hold.

Well, to start with, there’s a reason they call this variation a competition carbine. Take a match that mixes long gun and handgun skills in its courses of fire. Combine that with one of the many ranges in the country that do not allow high powered rifle ammunition to be fired. Voila: you have a situation where the pistol caliber carbine is ideal, especially if it is built on the same platform as the larger caliber rifle the shooter might keep for “more serious business.” While pistol bullets, even from a carbine, can’t be expected to do as much neutralizing damage as .223/5.56 NATO rounds or other more powerful AR-15 chambering options, the 16-inch barrel gives enough added velocity to turn 9mm into the equivalent of .38 Super with the same bullet weight.

RRA’s own 6-position Operator CAR buttstock gives a comfortable, sloped cheekweld, a textured rubber buttplate and two seperate QD sling receptacles.

Three-gun competition is not this writer’s game (a bit too athletic for old farts like yours truly) so I reached out to Kevin Williams. Kevin has earned a fine nationwide reputation as a police firearms instructor, but is also an avid and formidable competitor in Three-Gun and other action shooting games. Kevin told On Target, “Pistol caliber carbines are not used in three-gun much that I have seen. But the USPSA pistol caliber carbine division seems to be thriving. I have seen them starting to appear at IDPA.”

Another niche a firearm like the LAR-9 fits well is home defense. Like any AR-15 platform, its telescoping stock allows it to instantly adapt between the largest and the smallest member of the household authorized to access it for family protection. Another relevant quote from Kevin Williams: “I think this class of carbines offer a good choice for home defense. I say this because I had my mother in her late 70s try an MP-5 in semi auto and she had no problems shooting 4- to 6-inch groups at 15 yards off hand. She did find it a bit heavy. My wife while I was gone had the CZ (EVO carbine) loaded with a SIG Romeo 4M and ready to go. She had no problem hitting 8 inch plates out to 20 yards. I think these offer a better choice than shotguns and rifle caliber carbines for some.”

Mas found the LAR-9’s light weight up front lent itself well to one-handed “wounded defender” shooting, even in rapid fire. The same attribute also allowed for very fast tracking between multiple targets.

It should also be noted that the Competition Carbine’s conspicuous lightness up front will be a great asset for someone who may not have great upper body strength but has to use the carbine to hold a dangerous criminal at gunpoint for a while until the police can get to the scene to take over.

If recoil’s the same, why not just go .223 for home defense? Muzzle blast is the big difference. With a 9mm round out of a 16-inch barrel, the home defender is a lot less likely to suffer temporary or permanent hearing loss from the devastating reverberation of a .223 round going off in close quarters.


Perks n’ Quirks

Everyone on the test team liked the sweet, match-grade trigger pull. And they unanimously appreciated its muzzle-light fast handling. Some found the trigger a little light for self-defense, this after all being a competition target gun by its very name, but I’m sure Rock River would be able to provide on order an LAR-9 with a trigger that required a bit more pressure.

The 32-round magazines were difficult to fill by hand. You’ll want an UPLULA or similar product to assist, or the sharp feed lips will make themselves known to your thumb.

American Eagle 115 grain ball and economy Aguila 124 grain ball both grouped very well from LAR-9, with the American Eagle taking a small victory in group size.

As you can see, our quibbles were minor. Overall, the Rock River Arms LAR-9 is a very nice little 9mm carbine. We were impressed with build quality and overall performance, which were totally in keeping with its MSRP of $1,569. If you are looking for something that fills one of the pistol-caliber carbine’s particular niches, you definitely want to take a look at the RAA Competition 9mm carbine.

See it at your gun shop, or contact Rock River Arms, Dept. OT; Tel.: (866) 980-ROCK; Web:

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