M1941 Johnson rifle

Johnson M1941
Johnson M1941 Semi-Automatic Rifle with original spike bayonet and leather sheath. The 10-round rotary magazine could be quickly reloaded using two clips of .30 Caliber M2 Ball ammunition.
Type	Semi-automatic rifle
Place of origin	United States
Service history
In service	1941–1945
Used by	See Users
Wars	World War II
Production history
Designer	Melvin Johnson
Designed	1939
Manufacturer	Johnson Automatics, Inc.
Number built	~70 000
Variants	VF-1 (Argentine copy)
Specifications
Weight	9.5 lb (4.31 kg)
Length	45.87 in (1,165 mm)
Barrel length	22 in (560 mm)
Cartridge	.30-06 Springfield 7×57mm Mauser (Chilean variant) .270 Winchester
Action	Short-recoil, rotating bolt
Muzzle velocity	2,840 ft/s (866 m/s)
Feed system	10 round rotary magazine
Sights	Adjustable Iron Sights

The M1941 Johnson Rifle was an American short-recoil operated semi-automatic rifle designed by Melvin Johnson prior to World War II. The M1941 competed unsuccessfully with the U.S. M1 Rifle.

The M1941 rifle used the energy from recoil to operate the rifle. As the bullet and propellant gases moved down the barrel, they imparted a force on the bolt head that was locked to the barrel. The barrel, together with the bolt, moved a short distance rearward until the bullet left the barrel and pressure in the bore had dropped to safe levels. The barrel then stopped against a shoulder allowing the bolt carrier to continue rearward under the momentum imparted by the initial recoil stage. The rotating bolt, which had eight locking lugs, would then lock the bolt. Following, a cam arrangement then rotated and unlocked the bolt to continue the operating cycle. One disadvantage of this design was its impact on the use of a bayonet, as the complex movements of the barrel would be subject to unacceptable stress when a bayonet thrust was used. The Johnson rifle utilized a unique 10-round rotary magazine and a two-piece stock, the weapon using the same 5 round stripper clips used by the M1903 Rifle.

This system had some advantages over the M1 Rifle, including less perceived recoil and greater magazine capacity. Unfortunately, the Johnson's recoiling barrel mechanism resulted in excessive vertical shot dispersion that was never fully cured during its production life, and was prone to malfunction when a bayonet was attached to the reciprocating barrel. The Johnson also employed a number of small parts that were easily lost during field stripping. Partially because of lack of development, the M1941 was less rugged and reliable than the M1, though this was a matter of degree and was not universally opined amongst those that had used both weapons in combat.

As was Johnson's practice, he gave all of his weapons a "pet" nickname. Johnson christened his semi-automatic rifle Betsy and the Light Machine Gun Emma. A massive 20 mm aircraft cannon he developed for the Navy was called Bertha. Johnson referred to the Auto-Carbine as Daisy Mae. None of Johnson's memoirs or other writings reveals his inspiration for these nicknames, although at least a couple would seem obvious.