We are talking about the 7.62 X 51 right? Because an intermidiate cartridge of 7.62 x 51 and .223 Nato (5.56 x 45) has been around for about 60 years. Remember the 7.62 x 39R ? I was wondering wouldn't it fit for this intermediate purpose? Or is it too inaccurate at significant distance? Or some other draw back.