Mike378 proposed a theory to me 25+ years ago that the speed of penetration had a bearing on the frequency of speed kills. I saw that after he proposed it in the earlier X bullets which I started using in 1990.
I also saw it in very light for caliber bullet weights such as the 100gn in .270 and also at longer ranges of say 600 yards with 53gn .224's fired from the .223 Remington.
The face of an expanded petal has a ridge line that provides an additional cutting platform as well as the propeller effect JB raised. I have never seen or used synthetic testing medium but was fortunate to learn from flesh and bone which was a help also in the unlimited volume of culling which helped to learn this. John
When truth is ignored, it does not change an untruth from remaining a lie.
