I've not yet suggested that he go that route.
I'm hoping that we can clear it up with some pictures.
But the factory letter is how at least one "I've got a turbo rare gun, it's a Model 28 in .44 Special!" was solved...
Told the guy who had it that it was a gunsmith conversion, he refused to accept my analysis, but finally SORT of came around when he got the letter saying the gun left the factory as a 4" .357 Magnun, not a 6" .44 Special....
At the time it was made, S&W wasn't even making .44 Specials, so a Highway Patrolman barrel wouldn't have been marked .44 Special, and especially in a non S&W font.
It appeared that whoever did the conversion welded the old caliber marking and ground it smooth. Or they found a barrel that hadn't been marked with the chambering.
Anyway you cut it, though, it was a well done conversion. He picked it up at an estate sale for a good price, but unfortunately it didn't have any documentation with it.
"The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza
Baby Jesus cries when the fat redneck doesn't have military-grade firepower.