The M41 light machine gun was designed by a Boston lawyer and Captain in the Marine Corps Reserve named Melvin Johnson Jr. His goal was to build a semiautomatic rifle that would outperform the M1 Garand the Army had adopted. By late 1937, he had designed, built, and successfully tested both a semi-automatic rifle and a prototype light machine gun (LMG). Each shared a significant number of physical characteristics and common parts, and both operated on the principle of short recoil with a rotating bolt.
The Johnson LMG was one of the few light machine guns to operate on recoil operation and was manufactured to a high standard. The Johnson was fed from a curved, single-column magazine attached to the left side of the receiver. Additionally, the weapon could be loaded by stripper clip (charger) at the ejection port, or by rounds fed singly into the breech. The rate of fire was adjustable, from 200 to 600 rounds per minute. Two versions were built: the M1941 with a wooden stock and a bipod, and the 1944 with a tubular steel butt and a wooden monopod.
When firing, recoil forces along with the mass of the weapon's moving parts all traveled in a direct line with the shoulder of the gunner. While this in-line stock can be seen in the M16 rifle today, it was a novel idea at the time. Since recoil was directed back into the shoulder, muzzle rise was minimized. Due to this design, the sights had to be placed higher above the bore.
Johnson LMG in useThe Johnson LMG has many parallels with the contemporary German FG42. Both had in-line stocks, fed from the left side, and both fired from the open bolt in automatic mode and closed bolt in semi-automatic mode. Both weapons proved somewhat awkward to carry with a loaded, side-mounted magazine (especially the Johnson, which had a magazine with an unnecessarily lengthy single-column design), and this feature tended to unbalance the guns. Despite these similarities, there is no evidence that either weapon had any effect on the design of the other. Both machine guns attempted to solve similar problems, and adopted similar solutions.
Johnson was successful in selling small quantities of the M41 Johnson LMG to the U.S. Army and Marine Corps. One notable unit that used this weapon was the U.S. Army's First Special Service Force, a special operations unit composed of half Canadian, half American troops (nicknamed "the Devil's Brigade" by the Germans). The U.S. Marine Corps' 'Paramarines' also used the Johnson LMG.
Shortly after the 1948 War for Independence, the predecessor of the Israel Defense Forces, Haganah, developed a close copy of the Johnson LMG, the Dror, in both .303 British and 7.92mm Mauser calibers. Israeli forces found the Dror prone to jam from sand and dust ingress, and the weapon was discontinued after a brief period of service.
Melvin Johnson continued to develop small arms. In 1955, he was asked to assist Fairchild/ArmaLite in (unsuccessfully) promoting Eugene Stoner's AR-10 rifle with the U.S. Department of Defense, then with ArmaLite and Colt's Manufacturing Company as an advocate for the AR-15. Armalite relied heavily on Johnson's efforts and the AR-15 used a similar bolt design to the M1941 Johnson. The AR-15 is still manufactured today in the guise of the M16 rifle and variants. One of Johnson's last postwar firearms ventures was a 5.7 mm-caliber version of the M1 Carbine, aka 'the Spitfire'.