hatcher was full of it, he based most of his "formula" on LaGuarde's LIES about the "test' that he and Thompson did on a lousy 6 steers, back in 1907 or some such, with ridiculously out of date rds. 476 Eley, 38 long Colt, 455 Webley, stuff nobody knew or cared about by the 60's, much less today. The test proved nothing, because it was so egregiously out of spec in the first place. All 6 steers were still standing after 2 full minutes after taking 6 rds in the chest. the cadavers, hung by the neckl, "twitched a bit', when shot thru the chest with handgun rds, but no measurements were even attempted. the entire test result was published in the Gun Digest, `1981-82, I forget which. It's also been published, look for it at Ray Riling Arms Books, or used at amazon.com or in your library's BOOKS IN PRINT reference works. Read it for yoursel, and LAUGH at Cooper, Hatcher, Taylor and the rest of the 'momentum' bsing crowd.