So I stripped the thing down and polished up a few bits that moved against each other and the results were brilliant! groups are now less than an inch so there's still room for improvement but it's way better than the 4 inch groups previously!
I'll try to add some pics showing where I polished incase it helps anyone else.
What pellets do others use in their 586?
Cheers, Davy
http://www.davykelly.co.uk/wp-conten...5/IMG_2436.jpg
http://www.davykelly.co.uk/wp-conten...5/IMG_2437.jpg