I began rifle hunting with a smith and wesson 243, the ones made by weatherby back in the mid 80's ? this tack driver would shoot 1" group at 300 yds on a rest with custom handloads.......i put a 2x7 leupold on it and zero'd it at 300yds....bagged 5 point muleys that would feild dress 210lbs, while i worked, lived on ranch, sagebrush/farmland, i now live in the mountains, my question is this, if i buy a $1000 scope for my 6.5cm, can i zero it at 50yds, use it in the pine trees, then go back to flat land and dial it up to 750 yds for one of those muleys ?