I have been working with my Ruger M77 in .243 Winchester for a while now, trying different powder and bullet combinations to try and milk all I can out of it for velocity and accuracy with either the 55 grain NBT or the 58 grain Vmax. I have come to a load that is workable, but it is doubtful that it maximizes the potential of the rifle, with 46.5 grains of RL15 and the 55 NBT. It shoots right around m.o.a. at about 3,825 fps. Good enough for the coyotes it is intended for, but I have the sickness of trying to see what a gun can do...not settling for what will work. I have also tried H380 with the NBT and got better velocity, but no better accuracy. I have some Vmax's loaded up with the H380, RL 15, and IMR 4064 to try and I am going to put some NBT's together with IMR 4064 as well before I go on my next shoot. As I got thinking about utilizing all of the "tools" at my disposal I noticed that I have a full 1# can of H335 that I could try. I looked through my manuals (most of which don't address the bullet weight in question) and found H335 listed at the fastest (burn rate wise) powder for the 70 gr NBT in the Nosler #3 manual and also noticed it listed as being used for the 60 gr Sierra HP in the Hodgdon #26 Manual. It is also listed on the Hodgdon's website in conjunction with the 58 gr Vmax. So, although feasible, has anyone else worked with H335 in the .243? In addition, is there any other opinions on the powder itself? Thanks.