The use of 40mm cartridges as ammunition for individual and crew served weapons started early in the Vietnam War and has continued since with improvements in both the weapons and the cartridges used.
The 40mm round fills a gap between the capabilities of small arms and those of mortars or other supporting weapons. The 40mm cartridge family now includes a spectrum of capabilities including high explosives, anti-personnel, illumination, smoke, gas and other purposes.
USMC CPL Jason Desautels load a 40mm cartridge into his M203 Grenade Launcher/M16A2, Shoalwater Bay Training Area, Australia, 25 May 2001.
Today in WW II: 28 Aug 1941 Massive concrete Dneproges Dam and electric plant at Zaporozhyee on the Dnieper River [Dneprostroi Dam] are partially destroyed by retreating Soviet troops to prevent German capture [Operation Barbarossa]. More↓
The 40mm grenade cartridge is issued in two types for use with U.S. military weapons:
Low Velocity: 40x46mm cartridge used in individual weapons
High Velocity: 40x53mm cartridge used in crew-served weapons
The two types of cartridge are NOT interchangeable. The type specified for use with a particular weapon must be exclusively used.
The table below of Low Velocity 40mm Grenade Cartridges are used with the grenade launchers carried by the individual grenadier, such as the M79 Grenade Launcher, the M203 Grenade Launcher, or M320 Grenade Launcher. The table of High Velocity 40mm Grenade Cartridges are used with crew served grenade weapons, such as the Mk19 40mm Grenade Machine Gun. The tables are not exhaustive. New cartridge models are often introduced to meet new requirements or as improvements to older cartridges. Cartridges with "XM" in the model number are experimental, not yet type classified standard. Cartridges with an "I" suffix are improved versions./p>
Cartridge, 40mm Non-Lethal Extended Range Marking Munition
High Velocity 40x53mm Grenade Cartridges
M430A1 40mm HEDP rounds for the Mk19 Grenade Machine Gun, joined with M16A2 links. These rounds are packed either 48ea in M548 metal box (USMC pack) or 32ea in PA-120 metal box (Army pack). Al Asad, Iraq, 14 Jan 2007.
Each type of ammunition is color coded to distinguish it from any other similar rounds. There may also be notches, dots, grooves or other physical differences to aid distinguishing rounds in low light situations. More information can be found in the weapon's Technical Manuals or in publications such as FM4-30.13 Ammunition Handbook.
For example, the HEDP rounds can be identified by an olive drab casing, gold skirt and gold tip. Three evenly spaced indentations on the tip allow identification when visibility is limited. Upon detonation this shaped charge round has the capability to penetrate two inches of steel plate. The HEDP round is also a casualty producing round with an Effective Casualty Radius of five meters. HEDP rounds are self-armed by spin and set back action and must travel 14-28 meters from the muzzle before being armed. Once the fuze is armed it is very sensitive and will explode on impact. Care must be taken so that the round has a clear trajectory to the target (no branches, wires etc.)
Another example is the tactical CS grenade, recognized by its gray nose and red stripe. Six evenly spaced gaps in the extraction rim of the cartridge case allow identification when visibility is limited. It is used primarily for riot control and civil disturbances. Its maximum range is 400 meters. It will burn and release CS for 25 seconds on impact.
Vest, Grenade, Carrier (for Grenade 40MM)
The 40MM Grenade Vest is intended for use by the grenadier armed with the M79 or M203 Grenade Launcher. It is constructed of a seven ounce nylon fabric and weighs 2.1 lbs. empty. The vest is secured to the standard equipment belt with 10 belt loops, using hook and pile fasteners and snaps.
The vest has 18 permanently attached ammunition pockets that can carry 4 pyrotechnic and 14 high explosive rounds. The pocket covers are secured by one snap. A pull tab is used to open the pocket. The shoulders are protected by 1/2 inch (1.27 cm) foam padding. The vest closes in front with two chest straps using plastic quick release buckles. Two 2 1/4 inch (5.71 cm) webbing and two D-Rings sewn to the back of the vest can be used as equipment attachment points.
The vest comes in only one size and can be ordered under NSN 8415-01-317-1622. The specification number is MIL-V-44362.
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