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Canadian Forces Vehicle-Mounted Cannon — M242 25mm Chain Gun

Standard NATO 25mm shells - 12.7mm for comparison The M242 Chain Gun  —  Calling It What It Is ! [1]
Most automatic weapons operate using the propellant gases of  their projectiles.  The M242 is different  –  its operating cycle  (...load, fire, extract, eject...)  is entirely mechanical,  the bolt’s action being driven by a chain. M242 25mm Chain Gun

Coyote's 25mm Chain Gun - note pintle-mounted C6 The Chain Gun’s chain
The M242’s chain is powered by an electric motor. There are many advantages to this arrangement. Stoppages are minimized  (a mis- fired round will simply be ejected at the end of the cycle).  This electro-mechanical drive also means that rates of fire from the Chain Gun can be carefully controlled from single shots to bursts of 100rpm to 200rpm.

25mm Chain Gun in Delco turret Coyote 25mm - note high angle of elevation CF Applications for the M242 — Coyote and LAV III
The 25mm Chain Gun forms the main armament of both the Coyote ‘recce’ vehicle and LAV III APC – these two vehicles being fitted with the same Delco turret designed specifically for the M242  (and a coaxial C6 machinegun). The Delco turret has dual 25mm feeds allowing the most appropriate ammunition types to be selected by the gunner. The 1,100kg M242 has an effective range of 2,000m and packs a punch [2] despite its relatively small calibre.  So far, Canada has purchased 787 M242 25mm Chain Guns, all for use in ground vehicles.

See also — Coyote DFSV for a discussion of the 25mm M242 as a Direct Fire-Support weapon (replacing the Cougars with 76mm guns).

[1] In US service the M242 is called the Bushmaster, ‘Chain Gun’ being a generic term for Hughes-designed weapons of various calibres.
[2]  US combat experience has shown that, with repeated strikes of armour-piercing rounds, the M242 is capable of defeating early-model  Soviet tanks. Besides ground vehicles, US Chain Guns are also turret-mounted on helicopters or pintle-mounted aboard US Navy ships.

Photo Credits  — M242 side view, ammunition, and Delco turret: Stephen Priestley, other images: CF / Department of National Defence

  DND 101A Visual Guide to the Canadian Forces  2005 Edition


© Stephen Priestley 2001/2005