The law in this case does not differentiate between the landed gentry and others however, it is indeed an offence to discharge a "FIREARM" within a certain distance of a highway. I cant remember if it is 50 Yards or 50 Feet. Also, it relates to ALL firearms which includes air weapons !
BUT
If like rabbit pie how about this ........
"Pests Act 1954
14.23 Under the Pests Act 1954, the whole of England and Wales, apart from the City of London, the Isles of Scilly and Skokholm Island, has been declared a rabbit clearance area.
Within this area, occupiers of land have a continuing obligation to kill or take any wild rabbits living on, or resorting to, their land, or to prevent the rabbits from causing damage elsewhere by, for example, fencing them in with rabbit-proof fencing.
Failure to fulfil these obligations may lead to the occupier being prosecuted or the work carried out at their expense."