L30

L30
Gun of a Challenger 2 tank of the Royal Scots Dragoon Guards, Basra, Iraq, November 2008
Place of origin	United Kingdom
Service history
In service	1989–Present
Used by	UK, Oman
Production history
Designer	Royal Ordnance Factory, Nottingham
Manufacturer	Royal Ordnance Factories
Specifications
Barrel length	55 calibres (6.6 meters)
Calibre	120 mm (4.7 in)

The L30 is a 120 mm rifled tank gun used by the British Army and Royal Army of Oman. It is fitted in the turret of the Challenger 2 main battle tank. It is an improved production model of the Royal Ordnance L11 series of rifled tank guns.

The Challenger Armament or CHARM project was intended to provide a new main armament for the Challenger II tank and to be retro-fitted to the Challenger 1. It involved three components: the gun, developed by the Royal Ordnance Factory, Nottingham, the Depleted Uranium (DU) APFSDS round, and a propellant charge for it.

After earlier projects were cancelled, the EXP 32M1 experimental gun was re-titled the XL30E3 and accepted for production as the L30 in 1989.

The barrel is 55 calibres long (L55) and is made of electro-slag refined (ESR) steel. The bore and chamber are electro-plated with chromium to give a barrel life of 1,500 effective full charges.

The breech mechanism is a split sliding-block breech. One vertically sliding block holds the obturation ring (which is necessary because the propellant charges are combustible cases or bags) and is locked for firing by a second block. When the second block falls, the first is released to open the breech.

The ammunition types which are currently or were formerly in use include: