The Gammon Grenade

Because the “Sticky/Stickly Bomb” had a tendency to occasionally stick to its thrower instead a target, Capt. R.S. Gammon, a British paratrooper, invented an updated model towards the end of World War II that bore his name:

The basic design was to use a fuze, already available in the 69 Grenade, which was then inserted into the mouth of an elasticized stockingette bag. This bag could then be filled with up to 0,9kg of moulded plastic explosives which was part of the paratrooper’s normal equipment. The amount of plastic explosive varied according to the job for which it was designed. Priming of the detonation occurred when a steel ball dropped on the action of the bomb being thrown. Upon impact the bomb exploded. The fuze setting was originally a four second one through a weighted tape unravelling from the fuze after being thrown. Ordnance ‘boffins’ were appalled at the shortness of fuze, and the quantity of explosive that the bomb could contain, and accordingly ordered a seven seconds delay in order to ensure the thrower’s safety. However, most users preferred the shorter tape, irrespective of the danger involved, and cut the tapes back to a four second delay.

The Gammon Grenade ended up being terrifyingly effective:

During the invasion of Southern France in 1944 members of 5 Parachute Bn, in order to prevent movement from, or to, the beachead, took up positions in overhanging trees above access roads. Half-charge Gammon bombs, filled with road tarmac-mixing stones for anti-personnel purposes – in place of the customary plastic explosives – were dropped into open troop carrying vehicles with considerable effect.
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In military history it is renowned as being the only officially issued ‘do-it-yourself’ grenade.

The Grenade with Instant Fame [RapidTTP.com]