The reason I said to send it to the member that offered was for him to have a quick look over without taking anything apart as it could be an easy fix like something moved in transit etc and to someone who knows about these guns would be able to pick something like that up quite easily just by firing the rifle. With it being for your son for Christmas this could be the quick and easy way if not then send it to the manufacturer. The person that sold it could of already had it apart for all anyone knows so any warranty would be void anyway. I hope you get a quick resolve to this and your lad enjoys such a lovely Christmas present.