Clearly, this explains my inability to cop his tone! All this time I thought it was my abilities. Wow.
I did go back and look at the rig rundown where he talks about this and, sure enough, he says 1950 or earlier coins sound best due to composition. Smiling, he says “1947 was a particularly good year.” The coin, and Mr May, were both minted then!
It looks like the changeover began in 47, with the last silver one minted in 48. So, to get true MayTone from your pickcoin, go 1946 or earlier. This post so fits into the thousandth of an inch string discussion!