P38s need to be fed ammo that is around 1300fps. They have a bad habit of tearing out the eatractor/plunger/spring assembly if they are much hotter. They also will stovepipe if the velocity goes below 1200fps. Changeing your springs as was mentioned above (recoil spring) is most likely the culprit. If your ammo is to hot or light, that will also cause problems with stovepipeing. Another thing you may want to check, is the tip of the extractor sharp and complete, inside edge chipped away? bearhunter