The Mk 2/2 illuminating mortar bomb is a parachute-flared projectile intended to be fired from the British 2-inch mortar. It was used to light the battlefield at night for observation, artillery adjustment, or to expose enemy movement. Used during WW2, the British 2-inch mortar was actually invented in 1938. In addition to illumination shells, high-explosive, smoke and even practice variants were used.

This one here (inert of course) has plenty of numbers and marking on it, indicating it is a post war piece, made in 1966. The marking of 223 likely related to a lot number or serial code. Military codes and coding systems are famously elusive but taken on face value, we can determine that this is a post war piece, likely made in an Australian factory (perhaps Orange/Lithgow annex in Australia).

It is in a good condition, and all markings are clearly readable. Obviously the ‘head’ is missing, and the insides too as this piece is inert. The tail fins are present, not dented, buckled or damaged. Usually, pieces like this receive dents on their bodies through the years but not this one.

There are additional markings on the tail, which indicate the screw off tail cap were made before the shell, and also in a British factory. Eley-Kynoch, which is a well known British ammunition factory, and the 4/64 marking indicate April of 1964. The S marking is likely an inspectors stamp, and the ORB3 marking often indicate ordnance/acceptance codes or depot/factory identifiers.

In short, it’s a post war piece, made in the 1960’s and has British markings, and Australian markings too. Given that a LOT of Bren guns were made in Australia for the British, this isn’t strange at all.