Well, I was trying to let folks do their own research into the pain-bullet myth so as not to derail the thread. But since we're already here...
I think that the 'pain bullets are a myth' theory is an example of contrarian bombast. I think
...
Anyway, I could be wrong, just one man's opinion....
Well, I'd say the more bombastic position would be trying to make something more important than it actually is, specifically without evidence. It's pretty common in this hobby, particularly when we're first starting out. Every piece of unidentifiable iron dates to the earliest possible occupation of the site, every length of pipe is a gun barrel, every bit of horse tack is a colonial sword hanger (couldn't resist!), every coin was dropped the day it was minted, everything found remotely near a camp belonged to a soldier, every flat button was worn by a Confederate, everything with an eagle on it was military issue, every horseshoe and pocket knife was made in the 1860's, and yes - every bit of chewed up lead was clearly mangled in the mouth of a dying man in the throws of agony during a surgery (and yet miraculously not swallowed). I've been guilty of most of these at one time or another, trying to see something monumental in what amounts to a relatively less-than-monumental find.
It's not disproving an anecdotal theory to call "pain bullets" a myth, because there aren't any anecdotes to support the theory. Despite the incredible amount of writing during the era, there aren't any anecdotes about the use of bullets chewed on to relieve pain. Rather, it is disproving the wishful thinking of those who want that mangled bit of lead to be
more than just a mangled bit of lead.
The fact of the matter is, we don't know what caused it to become a mangled bit of lead. It's generally thought that the most likely cause of these bullets is wild or domestic hogs. There are probably a few out there that were chewed to induce salivation (there are a couple of accounts in the plethora of writing during the era that do mention this) or out of sheer boredom in camp. As much as we may want "our" chewed up bullet to have been from the soldier, we'll never know if any specific bullet comes from animals or humans.
But what we do know, is that it most probably wasn't used to relieve pain during a surgery. For one thing, despite common misconceptions, anesthetic was pretty common during the war and would have been the primary method of pain relief during surgery. Furthermore, while there are no "anecdotes" from the time period suggesting that a bullet would have been chewed during surgery, there are plenty of period medical textbooks which *specifically* mention not using anything in the mouth during surgery, particularly anything which has the possibility of aspiration.
Oh, and one last bit of "anecdotal" evidence for you. I once got to detect the Battle of Alamance with the NC office of state archeology. This War of Regulation battle saw less than 40 killed. And yet, a very large number of the musket balls we found showed considerable chewing. It's highly unlikely that the area of the battle was a giant field hospital (given the low number of casualties) with everyone chewing up bullets left and right. But you know what was there, after the war? A hog farm. Just sayin.
NOW, on to more high impact bullets!!