2230 seams too be the king of the hill at the moment the best I, have been able to do so far is 1” a with my Bushmaster using 60gr. Vmax and 25 gr. of it, but my tecnech is not that great and the bushie has a fixed fore end. My buddy is getting ¾” gropes from his Aremalite and ½” from his R.R.A. with the same formula.