.50 Beowulf
cartridge
The .50 Beowulf (12.7×42mmRB) is a 12mm caliber rifle cartridge developed by Bill Alexander of Alexander Arms for use in an AR-15 rifle.
Design and specifications
The cartridge utilizes a rebated rim, sized to match the rim of the 6.5mm Grendel round. The case body is very similar in dimensions to the .500 S&W Magnum revolver cartridge, being slightly longer and fully tapered for automatic feeding in the weapon.
The round is intended to improve stopping power greatly at short- to medium-range as compared to the standard 5.56×45mm NATO round. One of its advertised uses is against vehicles, being able to disable the engine and maintaining its trajectory when hitting windscreens or body panels. It's also advertised as being effective against body armor.
Design limitations
With normal bullet weights between 300 and 400 grains (19 and 26 g), overall cartridge length shorter than that of an AR-15 magazine well, and holding to pressures of 33,000 psi limited by the AR bolt strength system, the .50 Beowulf is best described as a low-velocity, heavy caliber, making its ballistics roughly equivalent to those of early .45-70 Government rounds rather than the higher pressure rounds tolerated by lever-action rifles such as the Marlin Model 1895.
Proprietary status
The .50 Beowulf is a proprietary caliber developed as a specialized cartridge. Alexander Arms and Delta Firearms oversee all aspects of the production of the system and related accessories. Their reluctance to divulge information has been a source of irritation to some writers.
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This entry incorporates text from “.50 Beowulf” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.