I have a customized 405 winchester and Im looking for some advice on different powders to use when loading. The rifle takes a full 3 1/4" Brass and the only Known load I have is for 300gn Barnes X. Im using 74 to 76gns of AA 2520 and getting 2600+ FPS at max load.
The question is. If I go to a bullet with more surface area like a 400gn X, what type of powder should I start with? 2520 is a medium burner and i am using Magnum LR primers. My current load of 76grns is producing nearly flat primers but im shooting out of a Ruger #1 so it will handle the pressure. I do not however want to over do it too much so with the ideas of using a barnes 400gn X bullet that has a longer length thus more friction would you go with a hotter powder with lower amount or a cooler powder and more amount?
Im also concidering a Hawk 270gn in .411 and it would have less friction than the barnes 300 X so the same question applies.
Anyone have advice here?