its much better now thanks guys, I seem to have isolated the cause and its thankfully not shooting I have moved my bus steering wheel closer to me so the arm isnt going out to full extension and it seems to have sorted it. Like my doc said it was always likely to be a repetitive thing that I did a lot and a couple of hundred shells at the weekend isnt really regular enough (to cause this, or for my liking ) but winding my steering wheel round for 10hrs a day was just the ticket.