The .458 HAM'R is a .458 SOCOM based caliber that was designed by Bill Wilson to push a 300 grain projectile 200fps faster than the SOCOM. Due to limitations of the bolt and extension of the AR-15, the .458 HAM'R is chambered in a hybrid AR platform that utilizes a larger diameter bolt and extension. This allows the .458 HAM'R to reach its full potential while still being a fairly lightweight carbine. Complete guns are available at Wilson Combat, and standard 458 SOCOM loading dies can be used when adjusted higher to acheive the proper headspace.