I have two 625's (a 5" Model of 1989 625-6 and a 4" JM Special Model 625-8). They are my favorite revolvers. However, I also have a Ruger SS 5 1/2" full sized Bisley .45 ACP/.45 Colt Convertible. It came with undersize throats in both cylinders. The .45 Colt cylinder with "standard" loads leaded terribly in just a few shots. The .45 ACP cylinder wouldn't accept my standard .45 ACP cast bullet loads with .452" bullets (couldn't chamber them).
However, after using a Manson "made for the task" cylinder throat reamer in both cylinders (.4525") now the revolver will, on demand, shoot groups from a rest with both cylinders well under an inch at 25 yards. This, with a variety of loads in either.
Just in case you think I am registering a complaint, I am NOT. Upon reflection, the undersize throats allowed me to tailor my throats for best results. Yeah, they should have been the correct size in the beginning, but they weren't. Being undersize was certainly preferable to being oversize.
This convertible has now become a prized piece of my shooting collection. It's a VERY useful piece for both the range and the field. I confess to shooting the .45 ACP much more than the .45 Colt as I am doing MUCH more "Range" than "Field" these days. Having one revolver that will "do it all" for a reasonable price and Ruger's ruggedness, is a real plus. Light target loads are a real pleasure and the ability to swap cylinders and loads for hunting is a big plus. I can recommend these convertibles to anyone who has been thinking about it.
FWIW
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