Thanks for the prompt reply.
I have not had the chance to go back to the shop with it yet as the full scale of the issue only came to light today at my clubs comp.
When i purchased it i had roughly 20 shot with it on their range and it behaved itself at that point so gave the impression of being fine. I intend to call them tomorrow to discuss the issue, but i just want to know who the experts are out there if i need to take it private. I don't want any tom **** or harry having a go on something they know nothing about. It isn't like putting a new spring in an SMK now is it