even if its 2nd hand mate from a shop you'll still have some warrentry ,,they have a duty to check the guns even if 2nd hand,, if they dont and they are selling faulty goods ,they are lieable under the sale of goods act 1979.. underneath is just a snippet for the act but 3rd line down may apply to you mate
the seller must
* Transfer possession by delivering goods in accordance with the terms of the contract i.e. on time and at the place agreed or if no agreement, at the sellers place of business and at a reasonable time.
* Sell satisfactory quality goods, which are fit for the