Crikey again 2½” Northover Projector This consisted of a hollow metal tube attached to a tripod, with a rudimentary breech at one end. Projectiles were fired with the use of black powder ignited by a standard musket percussion cap and it had an effective range of between 100-150 yards. Although it was cheap and easy to manufacture it did have several problems, ie it was difficult to move and the No 76 Special Incendiary Grenades it used as one type of ammunition had a tendency to break inside the breech, damaging the weapon and injuring the crew. Production began in late 1940, and by the beginning of 1943 nearly 19,000 were in service.
From memory, the 'prematures' were often down to using the wrong type of grenade. The glass No.76 came in two flavours, the thinner hand thrown version and one with thicker glass to withstand he shock of firing. They were colour coded but mistakes happen... Here's wiki: No. 76 Special Incendiary Grenade - Wikipedia
There's a story of a Yorkshire HG unit being forewarned that a regular Army unit tasked with HG exercises was doing the round's and being very rough with the 'part-timers' of the Home Guard. They managed to repulse their attack by firing multiple green apples from their Northover projector with great effect. Btw. 'Dads Army' was fiction...
