Originally Posted by TimSr
As far as energy being less than 9mm...huh? They are nearly identical balistically with a much better selection of bullet types for your .38.
For those who want proof the 9mm is more powerful (I'm using Speer Gold Dot because it is a popular defensive round, especially out of short barreled handguns):
On the Pocket Guns and Gear blog (aka Mousegunaddict) the blog owner did ballistic gelatin testing of both Speer's short barrel Gold Dot and the "regular" out of a S&W Shield. The SB Gold Dot showed expansion between .586"-.614" in 5 shots, ave 14" penetration, and with average velocity of 1109fps came out to 345ft/lbs of "impact energy". The "regular" God Dot expanded .519-.596", with 15.5" of penetration and 327ft/lbs of energy.
They did the same testing with Speer Gold Dot and SB Gold Dot for .38+P out of a Ruger LCR. The "regular" came out at .551" ave expansion, 12" penetration, and 225ft/lbs of energy. The SB came out at .563-.582" of expansion, 12.5" of penetration, and 221ft/lbs of energy.
Speer's own numbers (out of a 4" barrel so it doesn't account for the fact that revolver calibers often lose more out of a short barrel than auto calibers do) show similar differences. Non-+P 124gr 9mm comes out at 364ft/lbs of energy at the muzzle and 297ft/lbs at 50 yards. The 124gr 9mm+P comes out at 410ft/lbs at the muzzle and 324ft/lbs at 50 yards. The 125gr .38+P comes out at 248ft/lbs at the muzzle (less than the non-+P at 50 yards) and 220ft/lbs at 50 yards.
So, while expansion numbers may be similar, 9mm (both +P and standard) is superior to .38+P in both penetration and energy levels, while a 9mm auto provides less felt recoil than a snub shooting .38+P.