I use retumbo, federal 215 match primers, all RCBS reloading components and the 180 tsx with good results.
I would hit you tube and search the web for advice on reloading but found RCBS reloading step by step primer to be the simplest to understand and use combined with each components instructions. As far as load data most manufactures have data online that is trust worthy, Lyman's Reloading handbook is one of my favorite print references. Never had anyone to show me how, wish I did, as the previous post mentions this would be ideal.
Warning, the 300 is a great cartridge but not very fun to shoot vs. something like the 7-08 so your initial choice of powder will last a while.
Last edited by Sweetroels; 09-24-2013 at 04:56 PM.