The Hellfocker M-150 Battle Rifle, officially designated Rifle, Calibre 7.92mm, Model 150 is a full-calibre, semi-automatic or select-fire battle rifle designed and produced by the Hellfocker Arms Corporation, a Terran Inner Colonies armaments manufacturer. Introduced in 3266 during Great War, it was adopted by Marine forces and special operations units as a high-quality full-calibre service weapon, easily modified for a variety of tasks. The M-150 was introduced into general service, becoming the Army service weapon in 3273 and reaching peak general circulation in 3278. It was beginning to be replaced in general use by the AR-78 infantry combat assault rifle system, but this changed due to the Magellanic War and the experience of Union forces against a heavily-armoured and high-tech enemy infantry corps.
The M-150 is chambered in 7.92x57mm ISTO rounds, a military cartridge standardised in the Interstellar Treaty Organization at the behest of the Terran Empire in 2800, based off the similar 8mm Terran rifle round. The 7.92mm round was standardised across human space. Most Terran service rifles since then have used the 7.92x57mm round, whereas most assault rifles have been chambered in 7.92x33mm.
The M-150 has been noted as one of the most successful and effective rifles in the past century, renowned for its reliability and versatility.