AR-10 260 Remington

[ernierod]

Have a AR-10 Armalite-22" bbl-SS Bull bbl config.-1:8" twist.Am starting to develope accuracy loads for rifle using 139-142 gr bullets.I have the following powders-4064,4350,4831,RL19 and N150. Can anyone suggest a powder that I may try first to test for accuracy.Thanks for help

[runfiverun]

4064 is most likely best for operating the rifle.
the others may have higher port/muzzle pressure.
my take on it anyway.