I believe the bullets you have are Uni-Cor. Most of Speer’s 357 bullets are. The only 357 soft point bullets I see on their web page are Uni-Cor. I think they’re supposed to retain their weight better than conventional bullets. The jacket doesn’t separate because there is no jacket. Speer calls them bonded core (plated I believe). Suppose to work good. I us Gold Dots in 357 they're Uni-Cor too.
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