Not 25/223, but I shoot the Lyman 257420 in a 25-06. Best accuracy is 19.5gr 4198 with dacron filler at about 1950fps out of a 24" barrel. The flat point makes a distinct "plop" when it hits a ground hog. I also shoot the Lyman 257454 in the same gun, but the lighter bullet gives better accuracy. Kind of unexpected, as the gun showed a definite preference for heavier bullets when shooting jacketed.