A Wildcat Cartride I like: .30 ARX

    Now here is a wildcat that I can get behind. The .30 ARX is an immediately semi-auto AR-15 compatible cartridge. It’s nothing special from a manufacturing standpoint; as the cartridge creator claims, the .30 ARX is simply a necked-up 6.5 Grendel to accept common .30 caliber bullets.

    But, by changing the case from a .223 base to a 6.5 Grendel base, the user immediately gains 14 grains of case capacity (no bullet loaded) over the 300 BLK. This gives shooters using the right powders the ability to get to nearly 30-30 load performance while still being able to use the relatively common 6.5 Grendel bolts.


    Personally, I like this over the 300 BLK, simply from a mechanical design standpoint. While there is the issue of less common components, the higher-taper cartridge will make feeding and extraction more reliable. Plus, it solves what I consider one of the detriments of 300 BLK, its lower supersonic velocity (again, relatively speaking).

    The .30 ARX is still a wildcat loading, but tools are available for the reloader to easily manufacture this round at home. Those interested in the cartridge can see more details, purchase dies and other components, and check load data at AR-X Enterprises. 

    Nathan S

    One of TFB’s resident Jarheads, Nathan now works within the firearms industry. A consecutive Marine rifle and pistol expert, he enjoys local 3-gun, NFA, gunsmithing, MSR’s, & high-speed gear. Nathan has traveled to over 30 countries working with US DoD & foreign MoDs.

    The above post is my opinion and does not reflect the views of any company or organization.