Brings back a lot memories, I used to dig them up by the hundred at times when out metal detecting many had corroded, but around a dozen or so were like new after a good clean, the other bits to survive were the fins and the detonator part that the cap screws onto........ these all varied in condition though, other finds were parachute flares some complete with parachute and smoke bombs also about 5 complete HE rounds that never detonated.
I wrote not long ago about how the flare part lit up the village when I threw a bit on the open fire......
There was another type of cap which was the same but half the size, only ever found a handful and where in a different location can't remember what they were off.