Once a weapons platform seems to have reached its max design efficiency, the hardcore gun Jedi begin to look at ammo. The history of firearms is replete with countless wildcat cartridges that were designed to bring something more to a weapons platform. While it happens in handguns, it is primarily seen in the rifle world. This is exactly the case with the new rifle from American Tactical Importers (ATI) with their Omni Hybrid Maxx 6mm ARC.

The ATI Omni Hybrid Maxx 6mm ARC

The rifle from ATI slips back into an area many have dabbled with—a reinforced polymer receiver and aluminum upper. This design has had both fans and detractors, but it is undeniably unique.

The ATI 6mm ARC rifle features an 18-inch barrel and 15-inch M-Lok-style rail. The barrel has a 1-in-7 twist rate, a 5/8×24 thread pitch, and a flash hider at 5/8×24 pattern. It features an American Tactical SR-1 Rear Stock and a Nano Composite Trigger Kit. Beyond its polymer lower, its other unique feature is that it is chambered in the new 6mm ARC.

Design History

The 6mm ARC was one of the products Hornady brought to the annual Athlon Outdoors 2021 Rendezvous in Idaho. While there, I got the chance to talk quite a bit about ammunition. A little background on this unique round is in order if we are to really understand what is going on here.

On the surface, it may appear that Hornady, the designer of the cartridge, just decided to push out a new round. This is not remotely the case. The 6mm Advanced Rifle Cartridge (ARC) was designed to meet a request by the U.S. Military.

In fact, the 6mm ARC has unofficially been in service with U.S. Special Operations for almost two years. The exact units using the round are a piece of close-hold information for Hornady. They simply say it is being used by a “notable Department of Defense (DOD) entity.”

Hornady’s description is equally as cryptic. “The 6mm ARC has been tested, selected and fielded by a specialized group within the U.S. DoD for its multipurpose combat rifle program. The versatile 6mm ARC does much of what larger cartridges can and everything that smaller cartridges can’t.

“Designed to meet the needs of the world’s toughest critics, the 6mm ARC utilizes efficient, high-BC bullets to deliver unprecedented performance from the AR-15 platform. Commercial 6mm ARC offerings will feature bullets selected to deliver ideal performance for hunting, match shooting, and personal protection applications.”

This is a very unique situation where a round sees secretive service in the military before it is part of the civilian market. The 6mm ARC is based on the 6.5 Grendel. The designers necked down the cartridge to 6mm and then pulled the shoulder back closer to the case head. The case was also shortened to help make it compatible with low drag bullets.

The Goal of 6mm ARC

The question most people ask is why? What is the goal of the 6mm ARC? It’s really the same thing every cartridge designer has ever chased—a lighter round that performs like a heavier round.

The 6mm ARC is designed to do what much larger cartridges can and everything that smaller cartridges cannot. It is built to deliver substantially better ballistics than the .223 Rem. and offers a lighter gun/ammo system with 30 percent less weight than the AR-10/.308 Win. system.

In short, the round is designed to be effective in combat situations. This means it needs to perform at close-contact distance as well as longer-range engagements. With the bullet design, the 6mm ARC does this well. It stays supersonic past 1,000 yards and has demonstrated solid accuracy.

Range Report

The unique nature of the Omni Hybrid Maxx coupled with 6mm ARC had me anticipating range day more than normal. The setup was straightforward. I mounted a Tract Optics TORIC 4.5-30×56 34mm MRAD ELR scope and a bipod for stability. I would also be using a sand sock to finish out my shooting rig to improve consistency.

After a quick zero and target reset, rounds quickly began to fly downrange. In that Hornady is the only show in town for ammo, I shot both their Precision Hunter 103 grain ELD-X as well as the 108 grain ELD Match. Both performed well, but the Match ultimately gave me the best group at .75 inches at 100 yards.

Two major items became evident almost immediately. First, was the trigger on the rifle. For a budget realm gun, it was actually very nice and broke cleanly at just over four pounds. Second was the minimal muzzle rise and recoil. This was all about the ammunition at this point.

These two factors allow for not only accurate shooting but quicker follow-up shots. It was easy to stay on the scope and prepare for my next shot. This is one of the benefits of shooting a semi-automatic rifle in comparison to a bolt gun. While I have seen some people run a bolt like a rifle ninja, most people must come off their scopes to run the bolts thus breaking their shooting position.

The adjustable stock was a nice feature and greatly contributed to the overall accuracy of the rifle. Recoil-wise, the gun is a breeze. Most shooters would not notice any difference between the 6mm ARC and the standard 5.56. While the physics tells us running a 108-grain projectile does produce more recoil than a 55-grain projectile, the difference is negligible.

Running the ATI Omni Hybrid Maxx From Different Shooting Positions

I did not want to relegate the Omni Hybrid Maxx to being just a bench gun, so it was important to run it from a variety of shooting positions as well. I ran it from several other positions ranging from prone to kneeling as well as offhand shooting. In each instance, it ran well and provided solid accuracy.

The rifle is a lightweight shooter, but it is still easily manageable regarding recoil and muzzle rise. The ability of a rifle to run from a variety of positions is an essential part of serious applications. Very few real-world shots are ever taken from a prone or bench position.

In the world of lethal application or even competition, shooters are often required to shoot from odd angles and improvised positions. This is especially true considering the background of the 6mm ARC round. The weight and accuracy of the rifle are a solid fit for that application.

I wanted to get a feel for not only the rifle’s performance but the ammo as well, so I set up and started punching steel at distance. Targets I consider close, such as 300 to 500 yards, were child’s play for the rifle. This round, by design, is meant to be able to reach out and touch someone at distances a standard 5.56 may struggle.

The rifle and ammo performed as promised, and I soon found myself getting hits at 1,000 yards as well as the farthest target at 1,200 yards. At that point, I ran out of range but wished I could have found the fail point distance.

It is noteworthy to mention that this was shot on a clear Arizona morning with absolutely no wind or major environmental factors. As the disclaimer always says, “your results may vary.”

At Day’s End

Overall impressions of the gun were a mixed bag. The magazine included in the package was a .410 magazine from ATI’s Milsport .410 semi-auto shotgun. While the rounds did indeed fit, I experienced a few misfeeds.

I would ultimately replace it with an actual 6mm ARC magazine from someone like AR-Stoner. As I mentioned, the trigger was nice and better than I expected in a rifle with an MSRP of $949.

For those who already shoot in the 6mm arena, the question will be, “Why not just stick with 6.5 Grendel?”

Well, it comes down to what you want performance-wise. In all honesty, for the average civilian shooter plinking inside 300 yards, it is hard to justify. Where the rifle and ammo shine, however, is when you need to start reaching out at more serious distances.

Hornady ballistician Jayden Quinlan, who conceptualized the ARC shared this. “The farther out your target is, the more advantage you’ll see. For the guy who’s shooting at 200 to 300 yards, he has the advantage of a bigger bullet selection over the Grendel. For the guy shooting beyond 300, there’s a distinct advantage in hit probability and wind deflection.”

The fact that the lower was reinforced polymer did not seem to affect function or performance in any way.

Are Polymer ARs the Wave of the Future?

Do I believe polymer ARs are the wave of the future? I am not sure. There will always be durability questions, but I remember a little company back in the 80s called Glock that faced the same scrutiny.

Overall, the rifle performed well save a few misfeeds. The complete rifle is 100 percent made in the USA and assembled at ATI’s Summerville, South Carolina, facility. If you’re looking for an AR to join the 6mm ARC family, this may be something you’d have interest in.

ATI Omni Hybrid Maxx Specs

Caliber: 6mm ARC
Barrel: 18 inches
Overall Length: 32.5 to 35 inches
Weight: 6.2 pounds (empty)
Stock: ATI SR-1
Sights: None
Action: Gas-operated semi-auto
Finish: Polymer (lower), hardcoat anodized (upper)
Capacity: 10+1
MSRP: $949

This article originally appeared in the March-April 2022 issue of Tactical Life. Get your copy today at OutdoorGroupStore.com.