My BAR 30-06 shoots sub moa with the following factory loads: Hornady 150, Browning 155 and 180 grains and Win BST 168. Many of my handloads shoot sub moa as well, including Sierra 150 SP, Sierra game king HPBT 165 and Barnes TTSX 168.
I have noticed that the two first two shots almost touch with the BAR while the third is slightly apart. The reason is the increasing chamber/receiver heat after the second shot which increases the temp of the third cartridge. There are tow solutions for that: either shoot 3 shots very fast or take much time between the shots until the barrel/receiver/chamber cool down entirely. Anyway what really matters is the first two shots. In many of my handloads they touch.