Hi Paul,
I just finished working up loads for the 338/378 Weatherby with the TSX bullets and found that there isn't any load data for the TSX bullets yet. I also found out that the TSX bullets SHOULD have about 13.4% less pressure build up due to the grooves in the bullet. I don't know this for a fact but so far in my loading, it seems to be true. I used the Quickload program and loaded to the max pressures in Jesse's rifle with no pressure signs. Accuracy is great, ( 7/16" at 200 yards ).
I have an older Quickload program that came out before the short mags but it will give you a good starting point to start from. In the Barnes Bullet section, I only show the 450gr Solid and the 500gr X bullets that you asked about. All I need is barrel length, bullet, case capicity full to the top in grains of water.
For load data for your specific rifle, Email me at crystaleskies @ yahoo.com/
Let me know what you are looking for in what type of load you are working up. I try and keep most of my loads 100% full case and 100% powder burnt in the barrel. If you want something different, let me know.
Catch you later, The Big Dog
PS If you need more help than I can give you. You might want to see about getting the new Quickload from NECO. Their web site is
www.neconos.com/ . The program cost about $150 but is well worth it if you do a lot of reloading. To me and my friends it's like a virus. Once you start using it, you can't stop. It's answered a lot of questions for me without having to go out and do the testing myself. I think it is well worth the money.
The Big Dog