The absolute nastiest, rankest handgun I ever shot was a straight-blowback Astra in 9mm. Straight-blowback 380s are a close second. Just a fast, hard slap to the hand, with no unlocking mechanism to lengthen and soften the recoil cycle. Each shot was a stinging agony.
OTOH, I fired 50 rounds of .44 magnum with no problem. It was THE NEXT DAY that my hand and wrist paid the price.
yup- I'd rather shoot hot 357s out of my 2" taurus than .380s out of my girlfriend's Gaurdian .380-no fun at all.