It´s a strange coincident that you mention this figure. At the start of WW II the performance requirements for infantry rifles included incapacitating a cavalry horse at 600 m with one hit. The rifles had the accuracy to actually hit at this distance. I own a Swedish Mauser in 6.5x55. It still outperforms some modern scoped hunting rifles. Groups below 1 MOA are achievable with iron sights and the price for the ammo allows enough practice for good shooting.