So long as you keep your shots within your own property's boundaries, you should be OK. I have in the past read that some councils are somewhat anti-gun, however I don't think you will be breaking any law. From the Home Office document that offers guidance to the Police on firearms law:

Under section 161 of the Highways Act
1980, it is an offence for any person, without
lawful authority or excuse, to discharge any
firearm within fifty feet of the centre of any
highway which comprises a carriageway, if in
consequence, any user of the highway is
injured, interrupted or endangered. For these
purposes a carriageway means a highway
(other than a cycle track) over which the
public have a right of way for the passage of
vehicles. The Highways Act does not apply in
Scotland but Procurators Fiscal may use
common law offences of “culpable and
reckless conduct” and “reckless
endangerment” in situations in which the
1980 Act would be contravened in England
and Wales.