Is that red lock tite or some type of epoxy adhesive on the barrel and sight base?
My guess is the original hole end milled and tapped in the barrel was stripped - causing the sight to come off the first time. And, if it's lock tite or an adhesive, I suspect rather than installing a new barrel, they essentially "glued" the front sight base back on. That isn't really an option in a .45 Colt Blackhawk.
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If that's the case, it's consistent with my experience with Ruger customer service. I had an SP101 with an improperly cut forcing cone that resulted in extreme leading. The first time it went in they adjusted the extractor star and returned it, despite the ejector star having nothing at all to do with the described problem. Ruger promised to have one of their supervisors look at it and had me send it in again. They then decided it was not repairable and I had to wait 4 more months to get a new one the next time they made a run of SP101s.
I'm not such a Ruger fan when it comes to new Ruger revolvers. I love the old Ruger revolvers, and they seem to do a great job on their 1911s, but I won't buy a new Ruger revolver.