My AR15 also likes the 65 gr SGK. 24.6 gr of Varget. Shoots even better with 75 gr Hornady BTHP and 23.0 gr Varget.
Have also got good accuracy with 23.8 gr H335 with either the 65 SGK or 68 gr BTHP.
Another pretty decent load is the same 24.6 gr Varget and 60 gr Hornady SP which are only $14/100.
I tried Varget, H335, BLC2, and H4895 and Varget and H335 gave best accuracy. Have not tried accuracy test with anything under 60 gr yet but I expect any HP and H335 or H323 would be accurate.