Each barrel smith has his own method, but I suspect they were furnace brazed rather than soldered. Not that it matters a whole lot because this gun looks like a nice shooter, but yoke magnaflux would instantly show a distinct line, both at the breach and the joint between new tubes and original 'block'.

I doubt that they would be furnace brazed since they were demi-bloced with the bottom bloc brazed at the breech end & the rear & top ribs soft soldered. Trying to braze the sleeves in would more than likely make the breech end come apart.

Ribs aren't laid at that point, and they wrap the whole breech with iron wire.

I understand the process. Been there & done it many times.

So all this being said is there an explanation for one source saying it wasn't born a 28 gauge and another authority says is was born a 28 gauge.

Show me the source that says it wasn't born a 28 gauge gun. The letter told you how it was built. That's the way it left the factory.

It's obvious from your letter that it left the factory as a 28ga & some where down the road was sleeved with new tubes. To know if your doner barrel is original you need to look at the serial number on the barrel & see if it matches the serial number on the receiver water table. Also, is the number fonts the same on both.

He should be happy it wasn't sleeved to a 20ga or 16ga.

The comment was solely based on this sentence from the first page, "The serial number 131429 is not on the list of 28-gauge guns from the records, published in The Parker Story, page 1005. So, it likely started life as an 0-frame 16- or 20-gauge." Not having the book I made some assumption about its authority.

The thread then continues on to find all possible evidence that it was "retubbed", thus leading to my confusion. So apologies if offense was taken.

The "list" of 28 gauges is only one of the sources available to the PGCA researcher. Maybe it's time to repost the article that explains how the research material was found and how it was put into its final form.