I built my own 30-06 when I was in high school. Took an old military 30-06 and tore it apart. Put a Monte Carlo stock and a Weaver 3x9 scope and still have it today. Did all of my own reloading, so ammo was never a problem. Was able to get all of the military brass I wanted. Just had to ream out the primer hole and sometimes trim the brass, but it all worked.
I weighed 120 lbs soaking wet when I joined the Army. At that time the M-14 was a little much for me although I did manage to qualify. A year later I was in better shape and when I got orders for Vietnam and had to qualify with the M-16, I shot expert first time out. Quite a difference.