|Overview||Ghost Recon||G.R.A.W.||Future Soldier|
The M18 Claymore series are directional antipersonnel mines developed during the 1950s. Named after a large Scottish medieval sword. The M18A1 Claymore is the main production version and the most likely to be seen: it was adopted by the United States Military in 1960 and first used in Vietnam in 1966. Contrary to depictions in media which usually show it as rigged to a tripwire or proximity detonated, the M18A1 is almost always used in a command-detonated mode using the M57 "clacker" detonator (a small piezoelectric toggle generator based on an igniter developed by the US Navy for the "Tiny Tim" air-to-surface rocket) linked to the mine via a cable. Multiple mines can be daisychained to the same detonator. While they are not usually used in a self-detonated mode, it is possible to rig up systems to detonate the mine via other means: anything which can trigger a blasting cap will work.
The M18A1 Claymore mine has a horizontally convex gray-green plastic case (inert training versions are light blue or green with a light blue band). The shape was developed through experimentation to deliver the optimum distribution of fragments at 50 m range. The case has the words "FRONT TOWARD ENEMY" embossed on the front of the mine. A simple open sight on the top surface allows for aiming the mine. Two pairs of scissor legs attached to the bottom support the mine and allow it to be aimed vertically. On both sides of the sight are fuse wells set at 45 degrees.
Internally the mine contains a layer of C-4 explosive behind a matrix of about seven hundred 1⁄8-inch-diameter (3.2 mm) steel balls set into an epoxy resin.
When the M18A1 is detonated, the explosion drives the matrix forward, out of the mine at a velocity of 1,200 m/s, at the same time breaking it into individual fragments. The steel balls are projected in a 60° fan-shaped pattern that is 1.9812 m (6.5 feet) high and 50 m wide at a range of 50 m. The force of the explosion deforms the relatively soft steel balls into a shape similar to a .22 rimfire projectile. These fragments are moderately effective up to a range of 100 m, with a hit probability of around 10% on a prone man-sized 1.3-square-foot target. The fragments can travel up to 250 m. The optimum effective range is 50 m, at which the optimal balance is achieved between lethality and area coverage, with a hit probability of 30% on a man-sized target.