Originally Posted by SHÖCK
I must've tried a dud or had a near empty cartridge
More than likely so. Most people shooting it the first time almost have it jump out of their hand on the first shot the recoil is so powerful. The 'realism' aside in the aforementioned areas, this truly is a monster pistol with amazing performance and will be the closest thing to shooting real steel feel-wise most people will ever get.
Actually, the little Umarex (formerly by Crosman) Walther PPK and P99 compact are also quite a beast in terms of recoil. Although they're not as accurate as the Px4 since they're BB, they're still really fun guns to shoot.