This is probably the bullet of choice for most purposes, despite its poor SD. 175) without a cannelure specifically for the. Hornady designed a 250 grain FTX bullet (SD. 450 Bushmaster weigh between 240 grains (SD. 452 inch (handgun) bullet diameter, poor bullet sectional density (SD), lack of a roll crimp and headspacing on the case mouth are all inherent design limitations that degrade the cartridges reliability, performance and (potentially) safety. As you can see, the limitations inherent in the AR-15 action necessarily resulted in a compromised cartridge design. This is a warning from the people who developed the cartridge, so take it to heart. Using too much roll crimp can allow the cartridge to travel too far into the chamber and not fire, or worse yet fire with too much headspace, which can create an unsafe condition." "It is important NOT to use a heavy roll crimp when loading bullets with cannelures, like the 240 and 300 grain XTP-MAG. This prevents the use of a roll crimp, as used by most big bore rifle cartridges, to keep the bullet in place during recoil. Lacking a rim, shoulder or belt on which to headspace, the case must headspace on its mouth, like a typical autoloading pistol cartridge (.45 ACP, etc.). However, the Bushmaster has much greater back thrust against the bolt face, so be careful not to exceed the SAAMI pressure limit. 450 Bushmaster's MAP is 38,500 psi, considerably below that of the. The loaded overall cartridge length is 2.250 inches and the case takes small rifle primers. It is a rimless, straight wall case with a rebated.
45 caliber cartridge that would work through the short AR-15 action. 450 Bushmaster was designed by the Hornady Manufacturing Company for Bushmaster Firearms International when the latter wanted a.