What is the .270's claim to fame?
In my opinion, the advocacy of Jack O'Connor. It has pluses and minuses as it relates to the cartridges that bracket it from both above and below, just like all others. Had O'Connor, with his prolific writing of the day, used and wrote about one of those other "bracketing" cartridges so extensively, it probably would have had the same success in the pantheon of American cartridges.