The Act, as amended, tightens controls on the possession of firearms, and applies throughout the whole of the United Kingdom except for Northern Ireland.

The Act was passed in response to the Hungerford massacre of 1987, where sixteen people had been killed by a man using two legally owned semi-automatic rifles (M1 Carbine), (Type 56), and a handgun (Beretta 92).

The Act amended Section 5 of the Firearms Act 1968, which defined the class of prohibited weapons, by extending it to cover burst fire firearms,[1] semi-automatic and pump action rifles other than those chambered for .22 rimfire ammunition,[2] semi-automatic and pump action smoothbore guns other than those chambered for .22 rimfire and with a barrel shorter than 24 inches in length or an overall length less than 40 inches (to be measured without detachable stocks or with folding stocks folded),[3] smoothbore revolvers other than muzzle-loaders or one chambered for 9 mm calibre rimfire ammunition,[4] and finally any rocket-launcher or mortar which fired a stabilised missile.

[6] Additionally, section 1(4) of the Act gave the Home Secretary the power to prohibit any firearm or type of ammunition not on the list, provided that it had not been widely sold in Britain before 1988, and that it appeared to be "specially dangerous" or constructed so as to evade metal detectors.

[15] There were a number of specified exemptions to the requirement for a licence; members of approved rifle or pistol clubs were allowed to carry and use firearms when target shooting even if they did not themselves hold a licence,[16] and someone over the age of seventeen was allowed to borrow a legally held firearm from its owner and use it, under supervision of the owner and complying with the owner's licence, on private premises.