United Defense M42

Overview

United Defense M42
General Information
Type	Submachine Gun
Place of Origin	United States of America
Designers	Carl G. Swebilius
Manufacturer	United Defense Supply Corporation
Period Produced	1942 - 1943
Number Built	In 9x19mm Parabellum: 15,000 In .45 ACP: 6
In Service	1942 - 1945
Designations
Nickname	Marlin
Characteristics
Cartridge	Standard & prototype: 9x19mm Parabellum Prototype only: .45 ACP
RoF, Cyclic	700 rounds per minute
Expected Muzzle Velocity	335.3m/s
Action	Blowback
Feed System	Detachable box magazines
Ammunition Loading	25 round magazines, sometimes two welded together for quick reload
Dimensions
Weight	4.1kg
Barrel Length	279mm
Length	820mm
Stock
Stock Type	Full fixed stock

The United Defense M42 (sometimes known as the Marlin) is an American submachine gun with development starting in 1942. It was developed as a possible replacement for the Thompson submachine gun. The M42 was mostly used by OSS operatives.

United States of America Weapons Interwar & World War II Period (1919 — 1945)

Infantry Weapons
Melee Weapons	Blades	Ka-Bar • M1 Bayonet • M3 Trench Knife • M1917 Bayonet • M1942 Bayonet • Marine Raider Stiletto • Mark I Trench Knife
Sidearms	Pistol	HDM • M1903 • M1908 • M1911 (A1)
	Revolver	M1917 • New Service • Official Police • Victory
Close-Quarters	Submachine Gun	M1 (A1) • M2 • M3 (A1) • M42 • M50 • M55 • M60 • M65 • M1921 • M1923 • M1926 • M1927 (A1 • A3 • A5) • M1928 (A1)
	Shotgun	Auto-5 • M31 • M37 • M520 • M620 • M1897 • M1912
Rifles	Bolt-Action Rifle	M1903 (A1 • A2 • A3 • A4) • M1917
	Battle Rifle	M1 (E1 • E2 • E3 • E4 • E5 • E6 • E8 • E9 • E10 • E11 • E12 • E13 • E14) • M1941 • T1 (E1 • E2) • T20 (E1 • E2 • E2, HB) • T22 (E1 • E2 • E2, HB) • T23 • T26 • T27 • T31 • T35 • T36 • T37
	Assault Rifle	M1 (A1 • A2 • A3) • M2 • M3
Machine Guns	Light Machine Gun	Browning M1918A2 • M1941
	Medium Machine Gun	M1917 • M1919 (A1 • A2 • A3 • A4 • A6)
	Heavy Machine Gun	M2
Anti-Materiel	Anti-Tank Rifle	[[]]
	Recoilless Rifles	M18 • M20
	Rocket Launchers	M1 (A1) • M9 (A1) • M18 • M20
	Flamethrowers	E1 • E1R1 • M1 (A1) • M2 (A1)
Grenades	Grenade Launchers	[[]]
	Rifle Grenade Launchers	M1 • M7 • M17
	Anti-Personnel Grenades	Mk 2 • MK3 • MK3A1 • MK3A2 • M1 Frangible Grenade • T13
	Anti-Tank Grenades	[[]]
	Smoke Grenades	[[]]
Mines	Anti-Personnel Mines	M3 • M16
	Anti-Tank Mines	M1 • M1A1 • M4 • M7 • M7A1 • M7A2
Other	Flare Guns	[[]]
	Other Man-Portable Explosives	M1A1 Bangalore Torpedo

Infantry Equipment
Camouflage	Camouflage	[[]]
Clothing	Backpacks	[[]]
	Body Armour	[[]]
	Bomb Suit	[[]]
	Elbow and knee pads	[[]]
	Signals & IFF	[[]]
	Suits	[[]]
	Vests & Webbing	[[]]
Headwear	Communication	[[]]
	Gas Masks & Rebreathers	[[]]
	Goggles	[[]]
	Helmets	[[]]
	Vehicle Headwear	[[]]
Optics, Detection and Surveillance	Man-Portable Radar	[[]]
	Mine Detectors	[[]]
	Night Vision Goggles	[[]]
	Periscopes	[[]]
	Rangefinders	[[]]
	Surveillance	[[]]

Artillery
Anti-Aircraft Guns	M45 Quadmount • 37mm M1 • 37mm M1A1 • 37mm M1A2 • 40mm M1 • 3-Inch M1917 • 3-Inch M1918 • 3-Inch M1 • 3-Inch M2 • 3-Inch M3 • 3-Inch M4 • 90mm M1 • 90mm M1A1 • 90mm M2 • 120mm M1
Anti-Tank Guns	37mm M3 (A1 • 57mm M1 • 75mm M1897 • 3-Inch M5 • 90mm M2 37mm T3 • 37mm T7 • 37mm T8 • 90mm T8 • 105mm T8
Coastal Artillery	3-Inch M1902 • 3-Inch M1903 • 90mm M1 • 6-Inch M1897 • 6-Inch M1900 • 6-Inch M1903 • 6-Inch M1905 • 6-Inch M1908 • 6-Inch M1 • 6-Inch T2 • 12-Inch M1890 • 12-Inch M1895 • 12-Inch M1888 • 12-Inch M1900 • 14-Inch M1907 • 14-Inch M1909 • 14-Inch M1910 • 16-Inch M1895 • 16-Inch M1919 • 16-Inch M1920 • 16-Inch Mark 2 • 16-Inch Mark 3
Field Guns	75mm M1897 • 4.5-Inch M1 • 4.5-Inch T3 • 6-Inch M1897 • 6-Inch M1900 • 6-Inch M1903 • 6-Inch M1905 • 6-Inch M1908 • 6-Inch M1 • 6-Inch T2 • 155mm M1 • 155mm M1A1 • 155mm M1A1E1 • 155mm M1A1E3 • 155mm M2 • 155mm T4 • 8-Inch M1
Howitzers	105mm M1 • 105mm M2 • 105mm T2 • 105mm M2A1 • 105mm M3 • 155mm M1918 • 155mm M1 • 8-Inch M1 • 8-Inch M2 • 240mm M1
Infantry & Mountain Guns	75mm M1 • 75mm M1A1
Mortars	60mm M2 • 81mm M1 • 4.2-Inch M2 • 12-Inch M1890 • 36-Inch Project 4712
Railroad Artillery	8-Inch VI • 8-Inch M1888 • 10-Inch M1895 • 10-Inch M1888 • 10-Inch M1900 • 14-Inch M1920
Recoilless Guns	[[]]
Rocket Artillery	[[]]
Siege Artillery	[[]]

Land Vehicle Weapons
Vehicle Machine Guns	M1919 (A4 • A4E1 • A5) • M2 (Fixed • Flexible • TT)
Standard Tank Guns	37mm M5 (E1) • 37mm M6 • 37mm M1924 (A1) • 75mm M2 • 75mm M3 • 75mm M6 • 3-inch M5 • 3-inch M6 • 3-inch M7 • 76mm M1 (A1 • A1C • A2) • 76mm T1 • 90mm M3 (A1) 37mm T21
Other Cannons Mounted on Tanks	75mm Howitzer M1 (A1) • 75mm AT Gun M1897 • 105mm Howitzer M2 • 105mm Howitzer M4 • 105mm T8 • 155mm Howitzer M1918 • 155mm Howitzer M2
Rocket Artillery	M17 • T34 (E1 • E2) • T40
Vehicle Flamethrowers	E7-7 • E9 • E14-7R2 • Navy Mk.I • Ronson
Spotlights	Canal Defence Light

Aircraft Weapons & Munitions
Aircraft Machine Guns	AN/M2 • M3
Aircraft Cannons below & including 30mm	[[]]
Aircraft Cannons above 30mm	37mm M4 • 37mm T9 • 37mm M10 • 75mm M5 • 75mm T13E1
Aircraft Rockets & Missiles	T64 H.V.A.R.
Aircraft Bombs, High Explosive	[[]]
Aircraft Bombs, Anti-Personnel	[[]]

Naval Weapons & Munitions
Naval Machine Guns	M2
Naval Cannons below & including 30mm	[[]]
Naval Cannons above 30mm	37mm M9