You have to experiment and find the Sweet Load for your MLer, you cant just expect to load what you have and have it put 1"groups at 100yds, unless your real Lucky. I have Zero Experience with a Traditions MLer, but I do use the 240gr XTP and it works well for me. What Sabots are you using with the XTP? I use the Black MMP HPH-24's with them. I also use Pyrodox Powder (RS) and also Pyro Pellets. With the Powder I use 110gr's but as mentioned try starting at say 85gr's and work your way up. Also you may get a Bullet that gives you excellant Accuracy but POOR Results on a Deer.
Ask 20 different Guy's on here what Bullet and Powder Combo's they use and you'll get 20 different answers. Only your MLer know's what it likes and You will have to find that out, after you do then it's all easy peasy. Also a Good Scope and a Good Rest is a must befor going other routes, make sure it's not one of them befor trying something else.
Best of Luck to You!
(BP)