I am curious about how the front clamp on Weaver clmp on is secured/tightened? One picture I saw looked like an allen set screw type. does it act as a set screw on the barrel itself? wonder if they damage or scratch the blued finish? tks.
On the Weaver, it is a two piece base, the front "clamp-on" barrel ring is placed on the barrel near the muzzle end, where the tapered barrel is narrower, then slid toward the frame. The rear sight must be removed so that the base can be attched to top of frame using rear sight screw hole. The front of the base is then attached to the barrel ring using an allen head bolt/screw. I have not ever removed mine to see if it has damaged the finish. The .30 Carbine has a mild recoil so I don't think that the barrel ring will cause any damage.
However, the first scope mount that I used on my Super Blackhawk was a similarly designed B-Square mount that used the rear sight cut (with sight removed) and had a clamp on the barrel like the Weaver. It would loosen up after firing 50 rounds or so and I would have to remove the scope to tighten it up and then had to sight the scope in again. I got tired of that pretty quick. In the bottom picture there is a shiny spot on the barrel in front of the frame above the ejector rod housing. That was made by the B-Square barrel ring; it would rub on the barrel when the screw attching the base to it would loosen.
The scope that I was using with the B-Square mount was a variable Bushnell Trophy; one of the older glossy ones. Nice scope but kind of heavy. I am using a 2x M8 Leupold with the TSOB. I've fired hundreds of rounds through it with out any problems.
I suspect that the problem with the original B-Square no-tap mount compared to the Weaver (similar design) is the difference in recoil. It could be that the combination of the 44 mag 300gr XTPs and the heavy variable Bushnell was just too much for the mount