The .450 Bushmaster (11.48x43mmRB) is a

rifle cartridge A rifle cartridge is a firearm cartridge (firearms), cartridge primarily designed and intended for use in a rifle/carbine, or machine gun. Types Full-powered A full-powered cartridge is a rifle cartridge used interchangeably between servic ...

developed by Tim LeGendre of LeMag Firearms, and licensed to

Bushmaster Firearms International Bushmaster Firearms International, LLC, is an American firearm manufacturer and distributor. The company's product line revolves around semi-automatic pistol and semi-automatic rifle, rifle variants of the M4 carbine, M4/AR-15 style rifle, AR-15 ...

. The .450 Bushmaster is designed to be used in standard M16s and AR-15s, using modified

magazines A magazine is a periodical literature, periodical publication, print or digital, produced on a regular schedule, that contains any of a variety of subject-oriented textual and visual content (media), content forms. Magazines are generally fin ...

and upper receiver assemblies.

History

The .450 Bushmaster is descended from the Thumper concept popularized by the gun writer

Jeff Cooper John Dean "Jeff" Cooper (May 10, 1920 – September 25, 2006) was a United States Marine Corps officer and firearms instructor. He is the creator of the " modern technique" of handgun shooting, and an expert on the use and history of small ...

. Cooper was dissatisfied with the small-diameter 5.56×45mm NATO (.223 Remington) of the AR-15, and envisioned a need for a large bore (.44 cal or greater) cartridge in a

semi-automatic rifle A semi-automatic rifle is a type of rifle that fires a single round each time the Trigger (firearms), trigger is pulled while automatically loading the next Cartridge (firearms), cartridge. These rifles were developed Pre-World War II, and w ...

to provide one-shot kills on big-game animals at 250 yards. Inspired by this, LeGendre developed his .45 Professional cartridge, and later built and delivered an AR-15 in .45 Professional to Cooper. Bushmaster requested the ammunition manufacturer Hornady to produce the .45 Professional cartridge for this project, but Hornady wanted to shorten the cartridge case and overall length to accommodate their 0.452 in. 250-grain pointed SST flex-tip bullet. Bushmaster and LeGendre approved the change from a 1.772 in. (45 mm) case and 2.362 in. (60 mm) overall length (OAL) to the now standard 1.700 in. (43.18 mm) case and 2.260 in. (57.40 mm) OAL. This permitted operation in the more abundant and popular AR-15 platform versus the AR-10 platform. Also, a name change to ".450 Bushmaster" was approved.

Loadings and ballistics

The .450 Bushmaster makes use of .452 in. bullets because the lower impact velocities and energies would not adequately expand the heavier jacketed .458 in. bullets. The cartridge is chambered in bolt-action rifles by Ruger, Savage, Mossberg, and Remington, Ruger's No. 1 single shot rifle, AR-15 rifles, as well as an AR-15 pistol by Franklin Armory. Ballistically, the .450 Bushmaster has a rather flat trajectory out to 200 yards; if the firearm is zeroed at 150 yards, the user can expect to see a rise of 1.8 inches at 100 yards, zero at 150 yards, and a drop of 4.9 inches at 200 yards. The cartridge fits single-stacked in a standard AR-15 magazine with a single-stack follower. A 10-round AR-15 magazine body yields a four-round magazine, a 20-round AR-15 magazine body yields a five- to seven-round magazine, and a 30-round body yields a nine-round magazine. Hornady, Remington and Federal now manufacture ammunition for the rifle, and Starline manufactures empty brass for

handloading Handloading, or reloading, is the practice of making firearm cartridges by manually assembling the individual components ( metallic/ polymer case, primer, propellant and projectile), rather than purchasing mass-assembled, factory-loaded com ...

References

External links

Hornady Manufacturing - 450 BushmasterArchived
2009-08-05)
Bushmaster .450 Rifle & Carbine - Bushmaster FirearmsArchived
2009-08-05)
Hornady Manufacturing Company :: Ammunition :: Rifle :: Choose by Caliber :: 450 Bushmaster :: 450 Bushmaster 250 gr FTX LEVERevolution
{{DEFAULTSORT:450 Bushmaster Rebated rim cartridges Pistol and rifle cartridges Bushmaster firearms

History

Loadings and ballistics

See also

References

External links