I've begun reloading for my Ruger SP101, and have about 400 brand new cases of 357 mag to get started with ... but I also have 500 once-fired 38 sp cases.

I was thinking of trading in the 38 sp cases for as many 357 cases as I could negotiate, thinking it is best to just use full length cases in my chamber. I thought I could always just load down the 357 cases to a good practice / range fodder load. BUT, I have a couple friends saying just to use the 38 specials.

Any thoughts on the matter would be appreciated before I stuff any of the 38's