Sometimes it's good to go back and visit old friends, and so that's what I did the morning. Without any question, some of the worst results I've ever gotten with a handgun cast bullet came with the Lyman 358429. My fondness for the Keith SWCs is no secret, but some of the early work I did (25+ years ago) with the 358429 was simply awful -- 6-12" groups at 25 yards, some shots were even keyholing, and a few missed the target completely! I was very confused because these results were obtained with a revolver that is a legitimate "one-ragged-holer" at 25 yards with good jacketed ammo. This led me to dig a little deeper to try to figure out why. I learned a lot working with the 358429. Long story short, it turns out to have been kind of a "perfect storm" -- a combination of tight throats, cylinder endshake, over-sized cast bullets, and less than optimal lubrication. Cast bullets sized .357" and lubed with 50/50 beeswax/moly grease shoot every bit as well as jacketed ammo. For .357 Magnum, the most accurate load I've found with the 358429 is 12.5 grains of 4227. I'm currently out of 4227, so this morning I loaded this batch with 2400. If at first you don't succeed, dig a little deeper, you might just learn something....