Kevan,
My T-3 Hunter in .338 gave me problems as well. I tried 225g interbonds intially and got poor results, I tried this bullet with several different powders. I believe some of the problems with this bullet are due to the length and the T-3s short magazine, so your 250g bullet probably creates the same excessive freebore as my gun. Two things changed and my groups became excellent! I had my buddy bed the recoil lug and I went too a totally different load, which made the difference I don't know, as I never retried the original load. My current load is over max. going by my current manuals, I got the recipe from an article by Bob Hagel who has done alot of shooting with this cartridge.
I am shooting 210g Nosler Partions over 75g of IMR 4350 in WW brass with Fed 215 primers, the overall length of 3.310". Temp. was -10 C, avg. velocity was 2940 fps, 3 goups of 3 averaged .65". I also tried 76 and 77g, velocity read 2965, 3020 respectively with groups continually opening although still averaging 1" with 76g, but opening to 2" at 77g. I am very happy with the 75g load and will see how it works in warmer weather. These loads showed no visible signs of high pressure other than the opening up of group size, extraction was fine and brass and primers look good, I didn't mic any of the case bases. If you decide to try this load work up to it as no two guns are the same.
Good luck, Homesteader