Although I only reload 357 brass for my 357's, I always buy bulk packs of .38 when it's a good price. I've fired untold thousands of 38 spl out of 357 magnums and never have an issue. To be truthful, I've never even experienced the "crud ring" people talk about. I always soak the cylinder with ballistol for an hour or so...3 passes through each hole with a bronze brush, and it's clean as a whistle. Dont think too much on it...just shoot em!