5-14-05 data: P3AT .380, 2.76" barrel, 90 gr. Speer Gold Dot bullet, 6.2 gr. Power Pistol, .970", [27kpsi QL] some cases get guppy belly bulge, mixed used brass, 1095, 1115, 1098, 1054, 1093 fps = 1091 average
1091 fps 90 gr = 238 foot pounds
6.2 gr Power Pistol is not finding the threshold a case bulets in a super light 380 and backing off 4%.
It is instead tolerating some case bulge. This is nothing I could let anyone else shoot if I don't know their case support.
Buffalo Bore claims 1100 fps for 380 90 gr +P from these short barrels, but I am told it chronos at 1050 fps.
I have tested a half dozen 380s and worked them up to failure.
I would put them in 3 categories:
1) Lightweight 380s; Ruger LCP and Kel-Tec P3AT, 71% more powder than max published due to feed ramp intrusion to .270", thin chamber walls, lightweight slide, and weak recoil springs.
2) Medium 380s; Kahr, Bryco, 119% extra powder
3) Heavyweight 380s; Colt 1903, Beretta 1934, 209% extra powder. 1187 fps with 158 gr [better than a 357 mag with that barrel length]
