6mm Max - The Best AR15 Cartridge Yet!

I shoot a lot of AR15 DMR (Designated Marksman Rifle) style competitions that require shooters to be fast, yet accurate out to 1000 yards. I’m always looking for a better cartridge that provides a good mix of speed, reliability, shootability, an accuracy at range. When shooting that far, one could argue an AR10 would be best, but the ammo cost, recoil, and increase in overall loadout weight is a non-starter for me and many others. It’s also become it’s own game in and of its own to see how much we can jam into that small yet powerful AR15 frame. Well, I was delighted when I was able to talk to one of my shooting heroes, Ray Helms of the X Ring, and learn about why he has been shooting the 6 Max for his competiton gun lately. Trusting that he knows what he’s doing, I dove in to my first 6 Max build and was able to shoot it at a Quantified Performance competition in WV in March. Man, did it perform well! It was a super windy day, and we shot out to 817 yards. On that stage, I did so well that I took 3rd place. My wind holds were very reasonable compared to those shooting 5.56 and I really feel like it gave me a leg up that day. Since then, I’ve been sold, and I plan on shooting this as my competition gun until something better comes along (but I don’t think that day will come for a while!).

Ok so why do I think it’s so great? First, it fits the standard AR15 bolt face design, and doesn’t require a non-standard larger bolt like the 6 ARC and 6.5 Grendel do. Being able to run a standard AR15 .378 bolt is a huge positive in my opinion, since this is the bolt size (and structural integrity) that the platform was designed around. Enlarged bolt face designs have been known to fail, due to reduced bolt lug size, and this is a risk to guns that we expect a lot of hard use out of. Being able to get the same case capacity in a 6mm design as the 6.5 Grendel (35 grains), with the standard AR15 bolt face, is a huge win and great discovery/innovation!

Because of the case capacity of the 6 Max, you can push heavier bullets faster. This gives you more energy downrange for hunting scenarios, and more ability to buck the wind in long range shooting scenarios (for me, this is critical in competitions!). For example, I decided to handload my comp loads to the 6 Max manufacturer published match load of pushing a 90gr Lapua Scenar 2900FPS. This gives 1681 ft/lbs of energy at the muzzle, compared to the 1250 ft/lbs a 5.56 55grain bullet gives even at 3200FPS! All in the standard AR15 platform, without jumping up to an AR10.

6 Max case on left, 6.5 Grendel on right

While the cartridge is still very new, it does have some drawbacks, and those are mainly around the lack of availability of the cases. Although I keep mentioning that it fits the “standard AR15 design” it DOES have a different parent case, the 350 Legend. This is kind of a niche round and there is slim availability for the required 350 legend magazines. After talking with the 6 Max manufacturer they stated they are working on developing more mags for the cartridge so I hope to see that coming soon. With all that said, you can still get all the components you need for the build, and the freedom pills, from the BC Precision Ballistics guys that developed the round. They have partnered with Sons of Liberty Gun Works down in texas and are chambering barrels in 6 Max and selling on their website, so there’s nothing keeping anyone else from doing their own 6 Max build.

To recap, the talking points are simple. I love the 6 Max because it’s the same size AR15, but you can push bullets faster and harder, getting better ballistics and energy down range. I think this is truly a revolutionary cartridge and improvement over the original design, without some of the drawbacks that the countless other variants have. If you decide to build one, I hope you enjoy it as much as I do.

-Mike

CEO of Quality Sportsman

Check out the full video review above!

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