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

    I founded TFB in 2007 and over 10 years worked tirelessly, with the help of my team, to build it up into the largest gun blog online. I retired as Editor in Chief in 2017. During my decade at TFB I was fortunate to work with the most amazing talented writers and genuinely good people!