My friend bought a T3 Lite Stainless in 300WM about a month ago. He was having trouble and only getting 1.5-2 inch groups with various handloads. I told him to make sure the barrel was floated. (Like Elkmen wrote.)
Problem solved.
It is now well under an inch with H4831 and Horn. 180 Spire points. (And Sierra 180 Prohunters and 155 Scenars with H4350.)
On my T3, I had to float the barrel and swap out the factory rings (They were slipping).
And if you haven't done it yet, the Limbsaver pad makes a world of difference.
Good luck.
