There was a time, in Canada anyway, when Hunter was fired for group. The record agg, at 100 yd, was in the low .4 range and was fired by Jay Winfield. I don't recall what he was shooting.
The small group record was held by Al Mirdoch and was a .125" group. Al fired this from a factory Remington 700 Varmint rifle .308. This was an exceptional rifle and Al steered it pretty well. He shot his own 168 grain bullets and used a sissy bag to absorb some of the recoil. GD