First round jams

Hello. New to the board, but saw this thread and I have the same problem with my P5 (serial # 0268XX). I have tried 8 lb. springs, and many JHP styles and weights. Manual loading, using the slide stop and even second round jams after the first round has fired. Some jam more than others, but none have my total confidence. No burrs I can see or feel. I have tried 5 magazines, 3 walther factory and 2 no names I picked up at a gunshow. The non-factory magazines work much better at avoiding the nosing down of the first round or 2. Before I send it to a gunsmith, any other suggestions? OCSEKE, did you solve your issue with first round jamming? I have never had a jam in a Sig or Glock in 1000's of rounds so I don't think it is my hold even though a Star BM also does the nose down thing with JHP, but it's a Star I got for less than $125. The FMJ's function fine and I love the way the P5 shoots and feels. Thanks for any suggestions.