In the U.K. anyone in possession of a gun must have the correct permit. There are four different types:
The Firearm Certificate – this is issued to U.K. residents and covers rifles and/or airguns. This certificate lists the firearm(s) possessed, and those allowed to be purchased or acquired, together with the quantity of ammunition that may be held, purchased or acquired. There may also be strict limitations on exactly where the firearm(s) may be used. This certificate will not entitle the holder to purchase automatic, semi-automatic (other than .22 rimfire), or pump-action (other than .22 rimfire) rifles. Any air rifle with a muzzle energy greater than 12 ft/lbs, or air pistol greater than 6 ft/lbs, may not be purchased unless you possess a Firearms Certificate authorising you to do so. Handguns are now effectively banned.
The Shotgun Certificate – shows the names and serial numbers of any shotguns possessed. There are currently no restrictions on the acquisition of shotguns, providing the details of any transaction are noted on the certificate, and the issuing police force informed. It is necessary to produce your certificate when purchasing cartridges. For the purposes of the certificate, a shotgun is defined as a smoothbore gun, with barrel(s) at least 24″ (610mm) long. Semi-automatics must have a magazine capacity of no more than two shots: this must be a permanent restriction, verified by either the London or Birmingham Proof Houses.
The Visitors Firearm Permit – shows the make and serial number of any firearm that a visitor to Britain is permitted to bring in to the country with them, or borrow whilst here. It is not possible to purchase a firearm with a Visitors Permit, but ammunition may be acquired if such authorisation is shown. Limitations on the type of firearm that you import are the same as for U.K. residents; and restrictions will apply as to where the firearm may be used.
The Visitors Shotgun Permit – lists any shotguns that the visitor may bring into the country. These shotguns are defined as for the U.K. resident; therefore it is extremely unlikely that any semi-automatic will qualify, unless it has already been to Britain, and been approved by the Proof House. Any visitor wishing to purchase or acquire a shotgun whilst in Britain, must ensure that the police force issuing the permit put the necessary “authority to purchase” on that permit, which must also be produced when purchasing cartridges.
Air weapons must be held on a firearms certificate in the following circumstances:
Where an air rifle has a muzzle energy of more than 12 ft lbs.
Where an air pistol has a muzzle energy of more than 6 ft. lbs.
Any air weapon with a muzzle energy below these levels may be held without a licence.
Any air rifle, air gun or air pistol that uses, or is designed or adapted for use with a self-contained gas cartridge system is prohibited. It is an offence to manufacture, sell, purchase, transfer or acquire such a weapon.
It is an offence, punishable by a minimum of 5 years and a maximum of 10 years imprisonment, to possess a self-contained gas cartridge weapon without the necessary firearm certificate to possess one.
A person under 14 may use an air gun under the supervision of a person aged 21 or over, on private premises with the consent of the occupier of those premises.
From 14 to 17
A person aged 14 to 16 may borrow an air gun from a person aged 18 or over and use it on private property without supervision. A person aged 14 to 17 may only carry an air gun in a public place if under the supervision of someone aged 21 or over and there is a good reason for doing so.
Anyone under the age of 18 may borrow and use an air gun for target practice as a member of an approved club, or at a shooting gallery for air guns or miniature rifles.