The .307 is a .308 Winchester with a rim. It was chambered only in the Winchester Model 94 Big Bore, with the beefed up frame. It is a very desireable varient of Winchester Model 94. You better not wait too long to buy it, because regardless of price it will not last long. Winchester lever finatics will pay through the nose for them. You can reload the .307 with .308 loading dies. The caliber has a very good reputation as an accurate and powerful hunting round.