Most LRN will expand when hitting something such as phonebooks, etc. provided they are the typical soft swaged lead variety. They also expand, somewhat, on ribs. SHHHHH, don't tell anyone.....they still work fine.......... if you have ever seen the slugs taken out of the body of JD Tippet, the Dallas cop that was killed by Lee Harvey Oswald, they were "pristine" compared to some I've seen come from others. My guess is because they were fired from a .38 S&W Victory model, not a .38 Special gun so they were a bit undersized and nearly "knuckle-balled". Seen way, way, way too many wounds with LRN to be convinced they are anemic and killed too many critters to believe they don't deliver decent wounds.