I've been following this a lot,, and one thing stands out. Very little about how the gun(s) actually shoot.
You have mentioned the 3rd one shoots pretty good for you,, but commenting you had to adjust the rear sight "too far to the right" for your liking.
And you've mentioned how you just recently filed the frame to "give the illusion" of it being straighter, and no more than what the factory polishing & such would have done.
Another comment,, was about how it appears how the hole in the frame may have been off center slightly. Causing the barrel to be off slightly.
If I may politely inject some of my observations of hundreds of guns over the last 50+ years.
I've seen canted barrels, where the gun shot very accurately.
I've seen & measured several guns, same models, from different makers, and NOT come up with identical measurements.
I've shot guns that by looking at them, they appeared to be very poorly assembled,, or finished.
But the final judge of a gun to me,, is the target. How accurate is the gun?
A perfect example is a Ruger Vaquero that I own. It's in .45 Colt. Looking at it,, the barrel is a little off in the way the front sight blade appears. Something not too uncommon in the shooting world when it comes to fixed sighted gun. A lot has been written & discussed about this for decades. Many people either "turn the barrel," or "bend the front sight" or whatever. Some have even had the barrels removed, the rear of the barrel re-cut & all then re-installed to where the appearance is "centered."
My Vaquero.
I tried several different loads, and it shot consistently "low & left." Yet,, it grouped VERY, VERY well. I took it to a good friend,, a member here,, (who currently can't get back on due to the computer upgrades & such a few years ago,) "sixshot" to shoot. I did NOT tell him what I was looking for,, but asked him to try it & see what he could do with it. He had zero knowledge of what I was truly looking for.
He too had it shoot low & left. Yet, at about 25 yds,, he had a small, one hole group. He wanted to buy the gun, has badgered me "gently" for years to get the gun. It's super accurate.
Instead of worrying about how it looked & trying to "fix" it, I did not want to possibly reduce the accuracy of the gun by any normal turning or bending.
I had my gunsmith gently open the rear sight channel just enough to center the groups. Then I worked on ammo to affect the point of aim/point of impact.
I can easily look at it & see it's "not perfectly aligned." And I'll NEVER send it back to Ruger or anyone to "fix" it's appearance.
I'll take accuracy & performance easily over looks anytime.
So,, in the case of your gun(s) I've constantly wondered; "What does the target say about the accuracy of the gun?"
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