I reload .357 cases until I see a split/crack in the case. This split/crack is usually at the mouth like Grizzlypeg says. Some of my .357 cases are on their 12th time through.....FWIW, I use a 125g jacketed bullet with 6.7g of Tightgroup.
With this powder/bullet combo, how does it feel? Is it on the 357 Mag side or more liek a 38sp. Just working on doing the same but my wife likes them light and I like them with a good bank and a bit of a buck.
Rick