4227 will work well enough for the .357 Magnum if you want to burn off some powder. It's accurate enough too for the most part. It's usually used in larger cases for Magnum type applications like the 460 Magnum and 500 Magnum but I know a guy who uses nothing but 4227 in his .44 Magnum rounds. I was much more popular back-in-the-day before we had all the "new and better" powders available to us. It does better with heavy-for-caliber bullets than light bullet applications from what I've seen. I would suggest loading 158gr bullet over 125gr bullets with 4227.

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