GUN. 7.62MM, LIGHT MACHINE, L.4. This is a Bren Light Machine Gun that has been converted from .303’ to 7.62mm. (NATO), imperial size being .308”. When we went over to the Rifle 7.62mm L.I.A.I. (Self Loading Rifle) in 1957, the standardisation of calibres became vital. It would be little use to have the rifle in one calibre and the light machine gun in another.
Royal Small Arms Factory at Enfield got to work to redesign the Bren L.M.G. to take the NATO round. A new barrel, the fitting of side plates to the gun body, (needed because 7.62mm was a rimless case while the .303” was rimmed), therefore, the L.4 magazine was narrower. It was designed to hold 30 rounds and could be fitted and used on the S.L.R. rifle then in use. A re-designed breechblock was fitted to the L.4. Rambo might scoff at a magazine fed gun as opposed to having belts of ammunition wound around the body but the trouble with a belt fed light gun is that the belted ammunition lies on the ground picking up dirt that is instantly fed into the feed mechanism and barrel chamber causing accelerated wear, not a problem using a conventional magazine feed.
The L.4 has a slower rate of fire than the L.7 G.P.M.G at around 550 cyclic rounds per minute rather than 750 cyclic rounds for the L.7. Cyclic is theoretical and means that if you fired the guns full automatic for 60 seconds, you would get through 550 or 750 rounds. Because of re-aiming, overheating of the air cooled barrel and magazine or belt change, 200/300 per minute would be considered normal for the rapid rate. The vertical magazine is the best feed position. It is out of the way when trying to adopt a low profile and the only slight disadvantage is the need for offset sights to clear the magazine. In 7.62mm Calibre, the L.4 was perhaps not quite as splendid a gun as it was in .303” but, it was amazing to see that during the Falklands War, much training took place with the G.P.M G but when push came to shove, it was the L.4 converted Bren that was most often seen with our forces. The high quality manufacture of the L.4 Bren will see its use in the world’s armies for many years to come, more amazing when nearly all of these were converted from Mk. 3. Bren guns made in 1944 or earlier. Now that is value for money.