Sorry I have NOT replied to my own thread. Turkey season quickly came shortly after posting my question and it quickly consumed all my time. Then the Pedersoli 10 gauge broke after only 6 shots. So here are some of my thoughts-
@Britsmoothy and
@wilded I examined the barrels very carefully with a light and a fly tying magnifier. The marks Britsmoothy referenced concerning bore diameter are not present on mine. However it seems to be a true 10 gauge as 10 gauge wads and cards fit correctly.
@Rifleman1776 and
@Britsmoothy Concerning loading of wads and cards through what appears to be a true 10 gauge with an improved cylinder and modified choked barrels, I had no real issues with the common cushion wads, nitro cards, thin felt wads, or overshot cards. The nitro cards did need to be inserted on edge. Otherwise no problems. Britsmoothy's way of thin o/s cards was a godsend. More on that in a bit.
On the sixth shot the left lock's tumbler broke the full cock notch. I have been able to find one for $51.95 shipped from Flintlocks Etc. I'll have it Tuesday. I also sent a polite email to Pedersoli explaining the issue. They got back with me a day after I bought the tumbler from Flintlocks Etc. They seem willing to ship one to me for free. So I should end up with two left tumblers for the price of one. Don't have a clue as to how the original broke.
As for the general condition and cosmetics of the gun, it is very, very nicely put together. No real complaints on fit/finish. We all know how Pedersoli can royally muck things up. Mine has silver coin finished locks with a waterfowl scene, silver coin finished tang, blued trigger guard, silver coin finished trigger plate, blackened triggers, and 'browned' barrels with twin brass beads. Now we all know Pedersoli's 'browning' is some form of ceracoat and it usually looks ok to very poor. However mine is different. It appears as though the exterior of the barrels was bead blasted and then ceracoated. This gives the ceracoat some texture. It also appears as though maybe they are using either a different shade of brown or applying it differently. It actually strongly looks like real rust browning.
As for patterns and poa/poi issues. Nitro cards and cushion wads are a 100% no go. They blow patterns to the point of un-usefullness. Including the SkyChief method. I mean truly terrible regardless of powder charge or shot size or amount. Good news is both barrels shoot to the same poi in both elevation or windage. This has always been one of my real concerns with sxs and over/unders. The other good news is Britsmoothy's method of powder + 4 thin cards/overshot cards with a touch of lube+ shot + 1 overshot card works fantastic. Great patterns from both barrels. I also discovered utuber capandballs method of powder + cornmeal + shot + 1 overshot card produces excellent patterns as well. You may ask how I was able to test the left barrel after the sixth shot. Well I had a trusted friend with me who held the hammer back at full cock while I held the left barrel's trigger back. After I acquired proper sight picture, I said "now" and he released the hammer. We did this with the upmost safety in mind and it was barely doable but we made it work.
So, I think it will be an excellent hunting arm after I replace the tumbler. I'm not happy that the tumbler broke so quickly but this is the first lock I've broken in roughly 33 years so I'll chalk it up to 'things happen'. Interestingly enough though, my serial number starts with a 'K'. This would indicate that maybe mine is a kit gun. I bought it new from Dixie. Maybe there is some truth to the Dixie versions of Pedersoli's being kit guns assembled at Dixie??