So you're saying the 605 cylinder is longer but not larger in dia. thAn the 85 ? Hope you weren't talking cartridges. The 64 is no beauty queen and not part of my 401k. Doubt if S&W would honor any warranty work on the old piece anyway. The Taurus 85 was a cheap trade in and I'm not too worried about their lifetime warranty even if they would honor it on this old of a revolver. With my monthly stimulus checks, buying a 357 now is not practical. Owning a retail gun shop and repair service for almost 30 years, that left me with a few idle hours to ponder things like this. An ugly hvy bbl +P Model 10 was my test base several years back, and putting calipers to a 357 cylinder and the 38, they were the same length. So, what the hey ? That 10 and this 64 and 85 would and did fire the 357 only as an emergency situation if I had packed 357 and no 38 by mistake. I'm sure I'm the only one having done that.
Back to the original question, is the metallurgy of the 605 stronger thAn the 85.