I am looking at working up loads for my AR-308 with a 20 inch barrel.
I have two powders, IMR 4895 and Varget. IMR is 38.2 grains and varget is 38.7 on starting loads supposedly to get ~ 2400 fps with a SMK 168gr. Primers are CCI and brass is Federal GMM, Privi and Winchester.
Should I start with those loads and work up? What percentage or grains should I bring my loads down from a standard bolt action load listed in the Sierra manual? TIA!