Introducing the 45 RAPTOR Cartridge for the AR-10

Master cartridge designer Arne Brennan, the original inventor of the concept that became the 6.5mm Grendel, has developed a new round for the AR-10 platform. The 45 RAPTOR case is a necked up .308 Winchester case with a case length and body dimensions of a .460 S&W. It packs a much greater punch (30+% more energy at 100 yards) than AR-15 big bore cartridges such as .50 Beowulf, .450 Bushmaster or .458 SOCOM.


The cartridge has been designed for hunting medium and large North American game with a semi-automatic rifle and a barrel 16″ long (or longer). Because it is based on the .308 Winchester case, the only modifications to a standard AR-10 is a .45 RAPTOR barrel, a special barrel extension and modified magazines. No other modifications need to be made, saving shooters money. .45 RAPTOR cases can be reloaded with .460 S&W dies and a .308 Win. shell holder. .460 S&W dies are standard products (ie. non-custom) and manufactured by Hornady, RCBS, Redding, Lee and Lyman. The .45 RAPTOR uses .460 S&W reloading data, which is published by Hodgdon, Accurate Powder and Alliant Powder.

45 raptor ballistics

45 raptor 2


Starline Inc. is manufacturing .45 RAPTOR brass for Raptor Shooting Systems. They have 100,000 rounds of new brass in stock, with more being delivered in 2014 and 2015. The retail price for the brass will be 79 cents per piece sold in 50 piece bags for $39.50.

The barrels are expected to be in stock sometime around Memorial day. I have not been given pricing for the barrels. I will write a post on pricing for the rifle components when they have been passed onto me.


Because only a few additional rifle components are required and it uses standard reloading dies, combined with its performance, this cartridge is both a cheaper and a superior performing alternative to AR-15 big bore cartridges. New cartridges come and go but I suspect this is a cartridge that is going to stick around for as long as the AR-10 remains popular.

Steve Johnson

Founder and Dictator-In-Chief of TFB. A passionate gun owner, a shooting enthusiast and totally tacti-uncool. Favorite first date location: any gun range. Steve can be contacted here.



    How does this compare to some of the lever options, like .444 and .45-70?

    • MemorableC

      Quick looks show decently higher velocity, at 300gr the 45 raptor used a 16 inch barrel to get the same 2250ish ft/s that a 45-70 and 444 get out of a 24

  • David_TheMan

    What is the benefit of this over .308?

    • Tom

      I don’t get it either. I’m trying to figure out what medium to large North American game could NOT be taken with a .308.

      • Laserbait

        Heh, silly Elmer Fudds… Not every gun and cartridge has to revolve around hunting. You should get out more!

      • Anonymoose

        The minimum for moose and brown/grizzly bear is generally considered .30-06. If you want to use a .308, be my guest, though.

        • Joe_Mahon

          I used a .44 loaded with 300 gr hard cast…..took her Alaskan hide just fine, although I admit I was scared shitless as the gun hit that first empty case on the second time around:-)) There is dead, and I guess there is also “full stop dead.” In the alders, it was a slug gun from that day on…..the moral is you use what you have on your hip or shoulder. No matter what it may be—use it well. That means practice. That means ammo availability. And, to each his own:-))

        • mbrosch

          Look at the numbers. A 30.06 and .308 are so similar that your not going to detect a difference. Something like 50 FPS.

          • Anonymoose

            I see you’re looking at M2 Ball and M80 Ball. When they developed the .308/7.62NATO they aimed for a smaller case that would replicate the performance of Garand-level .30-06, .303, and other full-power battle rifle cartridges. And sure, with present-day 147gr factory FMJs it looks about the same, but the Garand’s gas system wears out quickly with heavier loads (read: pretty much any normal .30-06 hunting ammo) or even the original ’03 Springfield-spec loads, so those FMJs are severely underpowered for the cartridge capacity. Going beyond that, you can push heavier bullets (220gr-250gr) with .30-06 at better velocities than are possible with .308 without getting into dangerous pressure levels (heaviest .308 factory load I have ever come across is Double Tap’s 200gr). Most people who’ve dealt with big bears would choose a .338 Win Mag or a 12 gauge with magnum slugs over a .30-06 even. I read a guide from the Alaska DNR recommending that you use .30-06 or .300 Win Mag as a minimum cartridge for grizzly and polar bear defense as well. Just because you can kill a half-ton monster with a nicely-placed .308 from a concealed position doesn’t mean you should go for the lower-powered option when you have to punch through its face while it’s trying to eat yours.

      • Gavin Greaves

        I’m trying to figure what game would not be taken BETTER by the 45 Raptor within its range, bigger holes are very good in hunting.

    • Hunter57dor

      From a reloading perspective, .45 bullets are WAY easier to find these days than .308 bullets.

      also, ya know, larger wound channel and higher mass projectile. if you don’t need to go past 300 yards or penetrate steel plate, why use a pointed projectile?

      • Joe_Mahon

        Placement? I’m kinda into that:-)

    • Bill J

      There are several states where you can not hunt with 30 caliber. Mainly central states like Indiana, they require you to use a 45 caliber or higher (might be 40 I can’t remember off the top of my head).

      • Good point. From the Raptor FAQ:

        Question – Is the 45 RAPTOR legal for rifle hunting in Indiana?

        Answer – Yes, with a maximum case length of 1.800 inches and caliber greater than .35, the 45 RAPTOR meets the regulations established by the State of Indiana for a rifle-hunting cartridge.

        • Bill J

          Ahhh it is .35 caliber. Good find Richard. I haven’t hunted there in 10+ years, just knew it was some weird caliber restriction where you couldn’t even use a 30-30, we all just took shotguns and used slugs.

      • Yojimbo556

        I had no idea we expanded our approved caliber list. Used to only be approved pistol calibers and rifles that fired the same.
        Indiana is now .357 or higher for rifles and .243 for pistols, though a Savage Striker in .308 is apparently frowned upon.

        • Did you mean those calibers to be the other way around?

          • Yojimbo556
          • Ah OK – weird. I guess they’re thinking .243 out of something like a TC Contender, and .357 out of a lever-action?

          • Yojimbo556

            The flip side of it is if you are hunting deer to protect crops you can use whatever you want, or so the DNR officer said. I quit trying to make sense of our hunting regulations.

          • mbrosch

            He did say Indiana…

    • Glancing at my Hornady load data, it looks like a .308 180 gr bullet will make up to 2500 fps with Varget or Win 760 from a 22″ barrel. On the other hand, the 45 Raptor is pushing a 180 gr Nosler JHP to 2800 fps from a 16″ barrel. The Raptor can also handle bullets north of 325 grains.

      Granted the inherent accuracy of a .308 is much better, and velocity will bleed off more quickly from the Raptor, but for throwing a wide hollowpoint up to 200 yards, the 45 Raptor looks like a fun choice.

      The .308 is obviously one of the best all around rifle cartridges made. But, I think there is a place for the Raptor also.

      • Steve (TFB Editor)

        Indeed, and Raptor is designed to leave a very big entry hole.

        • Mack

          with speeds its hitting, it will probably also make a pretty decent exit hole. penetration has to be pretty good!

      • Brian Fulmer

        This is neat, 450 Marlin ballistics for the AR platform. The 18.5″ Guide Guns are neat but out of production, only Browning still makes a BLR for the cartridge. I can attest the 450 Marlin is a GREAT bear caliber, so this fills out the hunting card for the AR platform. Makes me want an AR10 for the first time….

        • 762x52n8o

          .450 Marlin ballistics for the AR platform — yes, there’s two of them out already, the .450 Bushmaster and the .458 SOCOM. And those are in the Standard AR15 platform, not the large AR10 platform. Lighter, more maneuverable.

          • Dontgiveahoot

            …less powerful. RIF.

      • FourString

        the round itself looks like a biig .357 magnum

      • mbrosch

        There sure is; Right there in my gun safe.

    • mbrosch

      Since the Raptor .45 not only delivers 1500 ft/pounds of energy @ 200 yards, In a slightly modified revolver it digests everything from a .45 ACP through and including the original .450 S&W Mag. In other words; Raptor just improved the S&W .460 revolver, and made it THE must have prepper gun. And oh Man! Moon Clips! I do dearly love moon clips.


    How does it compare to the lever options, like .444 and .45-70?

    • clinton notestine

      seems like roughly the same as a .45-70 reloaded for a bolt action rifle so more powerful than a lever action

  • Rusty Shackleford

    AR10 as in Armalite’s version or the SR25/DPMS/CMMG version?

    • Laserbait

      Should work in any of them, as long as the barrel fits the upper receiver.

  • Anonymoose

    A while back Teppo Jutsu came up with a family of bottlenecked cartridges (.338, .450, and .470 Rhino) for the AR-10 and other .308 AR platforms, based on a shortened .500 Jeffery (.500 Phantom). I’m not sure what happened to them, but they only have the .500 Phantom listed on their site.

  • guest

    Does jedi-mind-trick-palm-swipe saying “this is not the potential subsonic cartridge with great properties you are looking for”

  • JJTX

    How many more impossibly priced gun calibers do we need?

    Are you guys kidding? Have you seen the prices of NATO calibers where you can actually get the ammo?

    • Duray

      It’s called “making your own.” Not all ammo comes from Bass Pro.

    • Laserbait

      As many as it takes! 🙂 Besides, it’s going to be cheap to reload for. A quick calculation shows it would be about 55 cents a round. Might even be able to use 308 brass that you have already laying around, saving even more.

    • mbrosch

      Ever heard of the UN Small Arms Treaty?

  • ColaBox

    More powerful then the Beowulf? I see the charts, but I have a hard time believing this.

    • Steve (TFB Editor)

      the .50 B is defined for the AR-15 platform, thats why.

    • Laserbait

      Easily more power than the vaunted Beowulf. I have the Beowulf, and love it, but it’s not exactly a 50BMG. 🙂 The Beowulf is only running about 35K psi (if I recall correctly). This Raptor should be able to much more pressure, as the parent cartridge is designed for ~50Kpsi and so are 308 Win rifles.

  • Jonathan Wright

    How long until Buffalo Bore makes a magnum version of this round with some ungodly penetration numbers?

    • Steve (TFB Editor)

      A more powerful cartridge could be definitely be made. This has been designed to be as cheap as possible to use and convert. No fancy bolts, buffer springs, gas systems, custom dies etc.

      • supergun

        This weak model is some pretty strong stuff. wow

  • BattleshipGrey

    I guess I “get it”, but with standard/common ammo prices still high, now isn’t the best time to introduce another medium range big bore cartridge. I’ve typically been the kind of guy that likes to stick to the commonly available stuff. Maybe this one will stick, though, who knows.

  • Christopher

    How would this perform or even fire out of a non AR 308? Some of us don’t have a whole lot of money for a new rifle just to shoot a proprietary cartridge.

    • Laserbait

      It would perform about the same in a bolt gun, or a single shot. That said, proprietary cartridges are probably not the best way to go if for those on a limited budget.

    • The pressures are too high for a standard AR-15.

      • Christopher

        What I was asking was if it worked out a non AR rifle all together. Don’t have money to buy an A10 when I could use my other 308 rifles. Although Laserbiat already answered that question.

  • Burst

    For everyone who has ever wished upon a star:
    “If only the .308 had more recoil…”

    • Laserbait

      Heh, like a 308 Win has a lot of recoil in the first place…

    • supergun

      I had a Remington 308 bolt action. Beautiful rifle, but it kicked like a mule. Talked my Father-in-law into shooting this beast. He shot it, and I thought he was going to whip my ass. The moral of the story is, I bet the AR10 doesn’t kick much. AR is the most beautiful rifle ever made.

  • Lance

    Too bad ammo will be astronomically priced.

    • Laserbait

      It’ll be cheap to reload for. And a pretty easy one to reload too.

  • sauerquint

    Well I hope they use .458 rifle bullets instead of .452 pistol bullets like the Bushmaster.
    You may find this interesting, a site I’ve found builds an AR-10 in 450 Marlin. It’s about 3/4ths of the way down:
    It appears they chose this cartridge because it fits in Ar10 mags.

    • RaptorOne

      Per your link, 450 Marlin out of 24-inch barrel, 300 Grain Bullet at 2000 fps


      45 RAPTOR out of a 16-inch barrel, 300 Grain Bullet at 2250 fps per

      • sauerquint

        It’s an improvement, but only if you can find it.

  • Hilmer Lindberg

    Rimless 460? Headspacing issues, anyone?

    • Laserbait

      Not when it headspaces off the case mouth, like every other rimless straightwall cartridge. They’ve been doing it for about 100 years now…

  • Brandon

    I say its great! The more new ideas and innovation in the industry, the better. If everything always stayed the same we would still be where we were 100 years ago. Not everyone has to like same things. If we did, the world would be a very boring place.

  • iksnilol

    Old idea, here in Norway we call it .30 Idiot. It is what happens when firing 308 in a 30-06 Mauser.

  • 1911a145acp

    Missed the boat- Should be named .460 RAPTOR- (no magnum). Re-name it, reintroduce it and make like 3 million dollars….

  • dan citizen

    Yet another neat cartridge made possible by the AR’s ability to switch uppers.

  • Lionheart

    Having to modify mags is the big negative i see to this cartridge, people want interchangeability with their mags and caliber’s thus why the .50 beowulf is attractive to a lot of people. Hopefully they come out with 45 raptor mags that doesn’t need modification.

    • TV-PressPass

      Thats exactly what I thought when I was reading though. Good, good, wait, modified magazines?

  • wry762

    Ermagerd. It’s big and shiny – I want one.

  • HK_USP_45

    Sounds great, but how ballistically similar is it to the .450 Bushmaster or the .458 SOCOM? Those two cartridges come in the compact AR15/M4 platform. I wouldn’t want similar ballistics in a much larger rifle. So while this sounds great in theory, and I’m sure the mall commando/.300 Blackout crowd will find he “Raptor” name appealing, I think I’ll wait and see how this one develops.

  • Dusty

    I think I would still buy 458 SOCOM. Going to need a dedicated upper, anyway; M-15 lower is lighter. 458 SOCOM uses standard m-15 5.56 mags that are already in possession. Special bolt mounted in a carrier assembly is part of the dedicated upper. Brass is available. Need a set of dies anyway unless the user is already firing the new caliber in something else? Dies are cheap. It only gets into $$Dollars when reloading is a new project.

  • Greek Preparedness

    Old is new again…..about 10 years ago I was toying with the idea of full length 44 and 45s magnum (based on cut 30-06 cases) for the AR10 platform using G3 magazines, to compesnsate for the need for room in the front of the magazine. (CMMG & Oberland Arms make such lowers). The idea is now lost somewhere in the Snipershide forum archives.

    Even so, there is nothing new elongating the 45 magnum, elongating the 45ACP. In fact 45mag cases where made by cut and inside reamed 308 brass.

  • Hurp Durp

    This round will have great success if it is offered in a hunting rifle (eg: a Rem 700). Many hunters would jump on this round instantly as it offers .45-70 performance in modern packages while being extremely easy to reload for (what the .450 Marlin should of have been). Not to slag the .45-70 but this round shares the same bullet with the .45 revolver family, has widely found brass, and offers a platform other than a lever action.

    I think the .45 Raptor is a really great design however I do not think the tactical market is the best fit for it. The .45 Raptor reminds me a lot of the .327 Federal which was a great CC round but it would of been a phenomenal hunting round if it was offered as such.

  • Dontgiveahoot

    I just wish they would stop beating around the bush and develop a round for the AR-10 that single-stacks in the double-stack magazines.

    You’d probably need a rebated rim to fit onto an ar-10 bolt face without compromising the strength of the bolt rim…

    On the plus side, you could hunt Chryslers.

  • Mehul Kamdar

    How does the round headspace?

    • Dchil

      Probably the case mouth. Like every other semi-auto chambered in a straight walled case.

  • walter12

    All these new types of ammunition are fine except for one big problem, no one can afford to shoot the stuff.

  • MasterCinder

    So what’s next? Exploding bullets? Hey I got it, mortars! The lowly 22 LR taken more deer and elk off of Montana back country hay stacks than all the 30, 40 or larger cannons out there! I even know of one decent blackbear taken that way. This is all marketing IMHO.