Do I understand , on a post mill 243, I could buy a 300 or 308
barrel, screw it on and use those rounds?? No other changes needed?

"We're all going to have so much [bleep] fun we'll need plastic surgery to remove our god damn smiles." - Clark Griswold

Remembering The 99
http://www.blurb.com/bookstore/detail/1163424