This thread is very interesting, and shows up some inconsistencies with FLOs from differing forces. When I applied for my first FAC, my FLO stated that under no circumstances would our Constabulary approve any rimfire for fox control. Minimum they would approve was 22-250 at that time, although some things may have changed since then.
As has already been said, land acreage is less important than topography and location - FLO offered to approve any calibre I wanted on the 50 acres I had at that time, and tried to persuade me that I probably needed at least a .270 because of the likelyhood of w