.510 Beck AR Drum Mag

What in the heck is a .510 Beck you ask? The .510 Beck is a big straight walled cartridge that was developed by Beck Defense, it is compatible with .308 platform AR-10 lowers but it needs a different bolt, barrel and magazines to function. They’ll be available in 327 grains all the way up to 680 grains. While Beck Defense developed the cartridge, Devil Dog Arms will be making the rifles for them and Lancer will be making the magazines. You can check out our coverage of the .510 Beck cartridge at the 2016 SHOT Show.

A sneak peek pic of a new drum magazine for the .510 Beck cartridge was recently released. The drum mag is actually based on the .308 50 round drum mags from X Products. Currently only a non skeletonized version is in the works but a skelentonized version of the .510 Beck AR Drum Mag is planned to help minimize weight. A confirmed release date or MSRP hasn’t been announced as of yet, but I’d imagine it would be around the same $300 range as X Product’s 50 round drum mags for the AR-10. Check out BeckDefense.net for more info and a release date. The .510 Beck cartridge itself is supposed to be available in the third quarter of 2016.


Ray I.

Long time gun enthusiast, archery noob, Mazda fan, Sci-Fi nerd, Whiskey drinker, online marketer and blogger. My daily firearms musings can be found over at my gun blog ArmoryBlog.com and Instagram.

Shoot me an email at ray.i@staff.thefirearmblog.com


  • sauerquint

    I understand needing a different barrel, that’s reasonable, but needing a different bolt and magazine is a ‘swing and a miss’. They’ve demonstrated that they just don’t get the core concept here.

    • Kyle

      Yup. I think a big part of the reason the .300 Whisper was so successful is that you don’t need to change much of anything out. Barreled upper and you are ready to rock and roll with your original gear. When I get an AR10 I’ll be waiting for the round that follows that same concept.

      • SlippedThroughTheCracks

        .300 Whisper was successful?

        • GD Ajax

          It has enough ripoffs to be considered successful.

          • Budogunner

            .300 BLK is successful, by my definition, because the ammo and barrels have made it into mainstream supply channels. From what I could tell, the whisper was kept closer to chest intellectual property-wise. That protected the owner’s interests but kept it a boutique round.

  • Malthrak

    So…who actually is going to bother with a $300 drum for what is sure to be a hideously expensive wildcat unicorn cartridge (that apparently won’t be available for months) where about the only compatibility you get with the base platform is the receiver?

    I mean, aside from the three guys that buy everything just because.

    • Sgt. Stedenko

      Nicholas C will buy on as long as he can attach a flashlight to it.

    • The morbidly curious, like myself. I haven’t even heard of this round until now. Perhaps TFB should do a more in depth piece on .510 Beck? And maybe a few other calibers of this nature?

      • I would also like a piece on big bore cartridges for the AR-15 and AR-308 platforms. I am kinda-sorta familiar with the choices for the AR-15 (.450 BM, .50 Beo, .458 SOCOM), but am way less familiar with the ones for the AR-308.

        • I’d also kinda want a piece about caliber conversions of established platforms other then AR’s; like Mini-14’s. Actually, especially Mini-14’s.

          • DrewN

            17 Rem, 204 Ruger, 223 Rem., 5.56 x 45 NATO, 6mm x 45, 6MM PPC, 6.5 Grendel, 6.8 REM SPC, 300 Black Out, 7.62 x 39 are all available for the Mini.

    • nova3930

      I know my enthusiasm for new AR cartridges is dropping by the day. 556 for two legged critters, 6.8mm for hogs, 300BLK when I want to be quiet and pick your 308+ for thump at longer range for me. I just don’t see anything else out there that does anything significantly better in the platform than those…

      • raz-0

        As some people interested in this cartridge (not necessarily even in the AR platform), it might squeak past some places big game laws regarding what ammo is acceptable to take certain game.

        Heck, there are .450 marlin AR guns out there. The stuff is niche, but there is at least a niche. If anyone thinks it is going to be the next big MSR cartridge, they are smoking something really strong.

        • nova3930

          oh I get the niche argument. 2 of my preferred calibers are arguably in that niche role. Its a personal fatigue thing on my part. You eventually get to the point where you wonder why you’re grabbing yet another uncommon expensive round to shoot, even if it does give you marginally better performance in some aspect.

    • Budogunner

      Wilson Combat customers?

  • Cal.Bar

    WOW! this thing makes the Edsel look good.

  • iksnilol

    If we’re using .510 Beck I doubt we care about silly things such as “weight”.

  • Brett

    I really trust a company who’s address is a pack n mail type place.

  • Evan

    What’s the point of making it a .510 and not a .500? Doesn’t that make it an NFA item? If so, it doesn’t seem worth the tax stamp and the hassle.

    • USMC03Vet

      Yeah I was under the impression anything over .50 was restricted.

      • Evan

        I know that there are exceptions, like 12ga shotguns, but I don’t know the scope of the exceptions.

        • May

          It’s mostly a case-by-case basis. The general rule is that for it to be a destructive device it has to be over .50 cal.

      • Daniel

        It is .50 when it leaves the bore. Same .510 dtc. Etc.

    • Sledgecrowbar

      If it uses .50bmg bullets loaded into Beowulf-style cases, then the nomenclature would correctly be .510. It’s not considered a destructive device as the bmg is officially recognized as .500″

      • Evan

        The pictures (look at the link) don’t look like .50 BMG bullets.

        • Don’t forget that there are older sporting cartridges in the 0.510-0.512″ projectile range. Prime examples include the .50-110 Winchester, .500 Jeffrey, and .500 Nitro Express

  • Sledgecrowbar

    It definitely feels to me like they’re putting the cart before the horse now. I want to see product on shelves before you push the accessory support. I’m interested in subsonic half-inch rounds out if the AR platform above the 600-grain practical limit of Beowulf but I want to have an ammo supply first, then at least two barrel manufacturers, and as many for any other proprietary parts like magazines, unless it comes out that I can dremel the mods into a standard mag. third quarter? stop advertising, I’ll be bored with your boutique toy by the time it’s available.

  • dave

    i wonder what kind of effective range this gets. the 50 beowulf and 458 socom big bore ar cartridges are limited to 200 yards despite all the wallop they pack. if it was capable of extended ranged i could see the appeal. but a 308 ar10 already has great power (unless youre hunting moose or maybe big bear) and range. and even then you can just buy heavier loads as long as the twist rate in your barrel can keep it stanle. what does this offer that a 308 cant do?

    • Xtorin O’hern

      600 grain subsonics, and probably 300 grain supersonics, think of this as the AR-10 equivalent of .300 blackout

      • Budogunner

        Assuming it cycles both without need of hardware or spring swaps.

    • iksnilol

      You could go with sabots to extend range.

      Also, .308 and 6.5×55 work just fine for moose. 308 class is the most power most people willl need.

      What it seemingly does offer is the possibility of subsonics that at 100 meters carry 2000 or more joules of energy (which means it would be legal to hunt moose in Norway with subsonic .510 Beck). Then again, 50 Alaskan does the same.

    • Cymond

      Not practical, of humane for hunting, but I saw this picture a few years ago.

  • Geoff

    Well said.
    Then they scoff when another 5.56 AR enters the game with “yawn, another AR”.
    More options are always welcome. I may not like them all, but choice is good for the consumer.

  • John Bear Ross

    Sorry if I’m a bit thick. Was the actual capacity of .510 Beck rounds in the drum stated?

  • Adam D.

    You’ll only need to sell your car to load one of these. 🙂