The M3 fighting knife was developed in 1943 and hundreds of thousands were produced during World War II. The knife was associated with elite forces such as the 101st Airborne who wore it strapped to the lower leg.
Soldier of the 492nd Automatic Weapons Battalion, Battery C, equipped with M-3 Fighting Knife in M8 scabbard (on top of dispatch case), 27 March 1943.
Today in WW II: 17 Oct 1941 USS Kearny [DD-432] torpedoed but not sunk by German submarine U-568, near Iceland, killing 11 sailors, the first American military casualties of WW II. More↓
The M3 Fighting Knife -- also called the M-3 Trench Knife -- had a 6.75 inch spear point blade with sharpened 3.5 inch false edge, a handle made of compressed, stacked leather washers with 6 or 8 grooves, and a steel crossguard and pommel. The overall length is about 11.7 inches.
The M-3 was very similar to the US M4 Bayonet used on the M1 Carbine. The M-3 can be distinguished from the M-4 bayonet by the straight crossguard on the bayonet vs. the angle in the M-3 Knife crossguard. Of course the bayonet crossguard has a hole for the M-1 Carbine muzzle.
The metal parts of early M-3 Knives were blued, replaced by the Parkerized finish seen on most M-3s.
M-3 Fighting Knife Markings
The M-3 Knife was made in three different patterns. The first pattern was stamped with US M3, the manufacturer name, and the date 1943 on the knife blade. The second pattern was the same but without the date (photo, left). The third pattern moved the undated markings to the underside of the crossguard, for example "US M3 Utica." The pommel may be stamped on the end with the U.S. Ordnance flaming bomb symbol. Collectors refer to the M3 as ‘guard marked’ or ‘blade marked’ in discussing these differences.
The U.S. M3 Knife was manufactured by a total of nine vendors:
Aerial (Aerial Cutlery Mfg. Co.)
Boker (H. Boker & Co.)
Camillus (Camillus Cutlery Co.)
Case (W.R. Case & Sons)
Imperial (Imperial Knife Co.)
Kinfolks (Kinfolks Inc.)
Pal (Pal Blade & Tool Co.)
Robeson (Robeson Cutlery Co.)
Utica (Utica Cutlery Co.)
M-3 Knife Scabbard
The original scabbard (or sheath) for the M-3 Knife was the leather M6, developed with the knife in 1943. The M-6 had a body made of two pieces of leather riveted together, with a metal shield near the bottom. There is a snap loop to hold the knife handle. The leather is doubled over and riveted at top to hold an M-1910 belt hook. M6 sheaths were often cut down to eliminate the metal hook at the top which interfered with strapping it to the leg, paratrooper style (photo above, right).
Within a year, the leather sheath was replaced by the M8 or M8A1 olive drab fiberglass body with steel throat, described on the M-4 Bayonet page of Olive-Drab.com.
Where to Buy the M3 Knife
Until their 2006 bankruptcy, Camillus Cutlery continued to manufacture the U.S. M3 Fighting Knife, available from knife dealers or eBay. Other companies have duplicated the design, such as the Boker M3 Trench Knife
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