Pet loads for 77gr. SMK's for my .223?

[MnYoteRookie]

Howdy All...

Picked up a few 77 grain SMK's (w/ cannelure) to try some longer distanse shooting. Just wondering if anyone had any pet loads for 500m plus. They'll be shot out of a AR with a 1:8 twist, 18" Kreiger barrel.

Thanks...

 

[Kino M]

try 24 grains of varget with a cci 450 primer seated at max COL and dont crimp!