Re: 1000 yard + load for .30-06
For the 175, my guesses include Varget, IMR4064, and IMR4320, as well as ole' reliable, IMR4895. W748 and W760 also fit in that set of choices, and R/S Big Game might be a keeper too. I tried BL-C2 and was not overjoyed.
My Garand load is 150/155's and 50gr of IMR4064. It's directly quoted from the NRA reprint for the Garand; which lists 48.0gr for the 168, and 47.0gr for the 175.
I have used the 180SMK and 180SGK in the .308 for midrange work, and found them to be very closely matched except for copper fouling. The SGK appears to use a softer jacket for expansion reasons, and fouls more.
Published government loads, which should never be taken at face value, list the load for the 150gr FMJ and 173gr LC Match bullet as both being 50gr of IMR4895. I would not go above 49gr for the 150/155, and 46gr for the 175, which are simply quotes from the NRA reprint. The NRA reprint loads are for the Garand, and may have been trimmed to make allowance for the Garand oprod.