If you don't think 20" is overpenetration, then you fell asleep too early during the bedtime story.
From Buffalo Bore Ammo website:
This 380 Auto+P ammo will better all American made 380 Auto ammo by 150 fps to 200 fps in all bullet weights we make. This is a serious improvement in this typically anemic cartridge. This 380 auto+P ammo is more powerful than the typical 38SPL ammo made by most American ammo makers and you'll get 7 shots of it in a small/flat/light weight 380 versus 5 shots out of a bulkier 38 SPL J frame revolver. Additionally, with the 380 you'll get much faster reloads and the little magazines are flatter than a speed-loader used for a J frame.
1. Item 27A/20 is a 100gr. HARD cast bullet with a flat nose. It is traveling over 1,150 fps out of my 3.75 inch BDA (Browning Double Action). We've used a flash suppressed powder for all three of our 380 auto loads so that you wont be blinded by your own gunfire if you have to shoot in the dark and since around 95% of all civilian shootings in America occur in low light, the chances that your own gunfire will blind you while you are trying to save your life, are good - we've eliminated this variable by using flash suppressed powder. We've also chosen a flat nosed solid bullet. The flat on the nose ensures that the bullet will cut/smash its way through flesh and bone and do much more destruction than typical round nose FMJ bullets. Round nosed bullets tend to slip and slide through matter, doing little damage as opposed to a flat nosed bullet. The flat nose not only wounds much more than a round nosed bullet, but it actually keeps the penetration straight and thus deeper. Notice the below velocities recorded from my personal 380 auto pistols. These are real world guns and thus the speeds are realistic and not exaggerated speeds produced from laboratory test barrels. What you see with Buffalo Bore Ammo, is truly what you get in the "real world", where it matters. You can expect 20+ inches of straight-line penetration in flesh and bone with this load. If you are worried about over penetration with this load, DON'T! You chose to carry a tiny under-powered 380 auto pistol and the trade-off is that you are now going to have to stay alive with that pistol and over penetration will be the least of your worries if you end up needing this gun to save yourself or your family.
1. BDA-3.75 inch barrel--- 1160 fps
2. Walther PPK-3.5 inch barrel-----1149 fps
3. Colt Mustang Pocket Lite-2.75 inch barrel---1072 fps
4. Keltec---1061 fps