I remember reading that article about the .270 Redding, a .308 necked down to .277 with a blown out shoulder.
What an impressive achievement. With a full length action and a 24" barrel, special dies, and many hours of experimentation with handloads, he finally achieved the same ballistics that you can get with a standard factory, off the shelf .270 WCF with a 22" barrel and factory ammo.