Northern Rhodesia , maybe ?

[natal01]

Lockdown gives one the time to do fun things, like sort and resort badges.
I recently bought a few Northern Rhodesian badges which included this white metal crossed rifles in a wreath surmounted by an Imperial crown. I was told that it was given for the best shot in the force ( in this case the Northern Rhodesian Police) . I suspect that it is badge used by various forces in the British Empire. Can anyone throw some light ..?
The NRV shoulder title has been in the collection for a number of years. If you told me that it was for a small, relatively unknown unit called the Northern Rhodesia Volunteers, i would happily believe you, but I can find no such unit mentioned. Can anyone nail this down for me ?
Many thanks
Mike