Charlie, I would have likely let someone else answer you on the Bucks but I was still on the thread when you posted so here goes.
Buck currently has TWO lines of 300 series models. One, the old ones, are all American made which is made with 420HC with Bos heat treatment the best known. The second, is made in China, under heavy Buck control, including heat treatment. This was done back in the early 2000's when Buck was moving it's factory to Idaho. It was mainly for the production of low price point knives to be sold by the "Mart" stores and that price point could have no discussion.
CJ Buck has personally stated that he hopes someday to move all production in country as they have some models recently.
That is the straight talk. Now speaking as a Moderator, please lets not get off the OPs purpose, I answered an individual if anyone has more to discuss on the subject please go to the Buck forum or my Bud Knarfeng and your moderator will kick my shin and shut this down. Thanks
300