Mossberg's entry into the AR field is the MMR, a direct-impingement design that is being offered in two different lines, Hunter and Tactical, to appeal to as wide a consumer base as possible. I tested the Mossberg MMR Tactical, an all-black model with 16.5-inch carbon-steel barrel with 1:9 twist and chambered for 5.56 NATO, as opposed to most domestic ARs, which are chambered in .223. (What's the difference? Check out this article.)
The Tacticals come with a quad-rail fore-end with your choice of fixed or adjustable stocks, 10- or 30-round magazines, no sights or detachable iron sights. I chose the model with fixed buttstock, iron sights and 10-round magazine.
The government profile barrel is manufactured by Mossberg in Texas and has the distinctive M4/203 cutout, in case you need to attach a grenade launcher at some later date. The rifle has a carbine-length gas system, and the 10-inch long quad rail fore-end extends a few inches past the low profile gas block.
Quad rails are popular not because of their looks but rather their performance. Want to attach a flashlight or a vertical foregrip? If it's designed to clamp onto a rail, you're all set. Quad rails can chew your hands up if you do a lot of shooting, but many companies produce either rubber or polymer rail covers in varying colors.
The barrel is tipped with a simple muzzle brake that amounts to a standard A2 flash hider, which instead of being open at the end has a flat with a center hole. While not as efficient as some brakes, it does reduce recoil (which an A2 flash hider does not do). In the early days of 3-Gun competition this GI-profile style of muzzle brake was the only kind allowed.
The rear sight is a standard A2 rear sight clamped on to the flat-top upper receiver. There is a detachable front sight supplied as well, installed at the factory at the end of the top rail. The rifle has a carbine-length buffer tube, with a permanently attached M4-style buttstock. It is supplied with a standard (not heavy) buffer.
Instead of a standard A2 pistol grip, the MMR is supplied with the Stark SE-1 Grip, which not only increases the distance between the backstrap and the trigger but has an integral oversize trigger guard. The pistol grip has a water-resistant compartment inside with slots designed for battery storage. The charging handle of the MMR is not GI standard but slightly oversized for better manipulation.
Inside the MMR appears to be totally mil-spec aside from its lack of a forward assist. The bolt carrier key is properly staked, and the carrier itself is the lighter semiauto AR type. Trigger pull was straight GI single stage, which means it was heavier and grittier than I would have liked but typical for an AR. The 10-round magazine supplied with the rifle was from CProducts, a well-known AR magazine manufacturer. It had a blackened stainless steel body and an orange non-tilt follower.
The MMR tips the scales at 7.5 pounds, which means it is light enough for shooters of smaller stature to handle yet heavy enough to tame the already anemic recoil of the .223. It's the quad rail that adds the extra weight, but that extra weight helped keep the muzzle on target during offhand rapid-fire strings.
Shooting the MMR brought no surprises. I started with quality magazines (in addition to the supplied CProducts mag), lubed the gun before testing, and had no malfunctions firing several hundred rounds over the space of a week.
Curious to see if it would show a preference for bullet weight, I tried everything from 50- to 77-grain projectiles. The rifle showed no clear favorites and shot most everything into groups hovering around 2 inches. I threw a Hi-Lux CMR 1-4X scope on the carbine for the accuracy work. This budget scope has good glass, and I probably could have produced better groups with a better trigger. I find I am able to do better groups when I combine a match trigger with a mediocre barrel than the reverse.
An MMR Tactical without sights has a suggested retail price of $885. Those with sights have an MSRP of $921. The fact that Mossberg's suggested retail is less than the street price of most of its competitors should come as no surprise.
- Type: direct-impingement AR
- Capacity: accepts AR magazines
- Caliber: 5.56 NATO/.223 Rem.
- Barrel: 16.25 in.
- Overall Length: 36.5 in.
- Weight: 7.5 lb.
- Finish: black phosphate
- Trigger: 6 lb. (as tested)
- Sights: removable front and rear on full-length Picatinny rail
- Price: $921 (as tested)
- Manufacturer: O.F. Mossberg & Sons
- Smallest avg. group: 77 gr. Black Hills BTHP — 1.47 in.
- Largest avg. group: 62 gr. Winchester FMJ — 2.19
- Avg. of all ammo tested (5 types) — 1.96 in.
- Accuracy results are the averages of three three-shot groups at 100 yards from a sandbag rest.