If you mean galling on internal parts on older stainless S&W's, I've heard of it. They cured it by replacing the stainless hammer and trigger with carbon parts, flash-chromed.
As far as I know, Ruger's stainless parts never gallled or otherwise caused trouble. Different alloys and heat treatment.
My own M-66-3 was bought new in 1990 and has been carried most days since until I left security work last month. It has never caused a bit of trouble and is very accurate. It is probably my favorite handgun of all time.
However, I had a M-64 made in the '70's, and it never had problems, either.
Keep in mind that early M-66's jammed when the gas ring expanded from heat. .38 ammo wouldn't cause that, just a number of .357's. Massad Ayoob blew the whistle on this in gun magazines, and S&W moved the gas ring and solved the issue. I think that either -1 or -2 guns incorporate the change.
I like the M-66 very much as an all-round handgun. But I don't fire vast amounts of .357 ammo in it, and avoid the scorching hot 125 grain and lighter bullets, which cause added wear and may crack forcing cones. I prefer the Ruger GP-100 or S&W M-686 for frequent use with full Magnum ammo.
