Came across this amazing piece of ordnance in New Zealand today

i gather its Boer War, its a 15 pounder with a time fuse of the period
The most fascinating part to it…… is it has a grappling projectile inside the round.
i say grappling because thats what it looks like it could be used for.

Fuse marks- 10/00 R(arrow)L IV 722 p
Steel Fuse part- S5
Timer - 0-18 , (inside time has a) - N D
Round base- 15 DR III, F S, RL
Driving Band- K, BCO

Can anyone help identify it or point us to reference they might know of that might mention this type of ordnance being used.

i have posted lots of pictures of it. im sorry if its too many