Hi all im new here and to shooting . I recently bought a used m&p shield for my carry weapon. As far as I can tell on the box it was made on 4/417 so less than a year old. I was shooting winchester 124 grain fmj nato 150 round box from wally world. I have never used that ammo b4 . In the first 3 mags I had 2 duds and a stove pipe. I was not sure weather to blame the gun or ammo? I have not had a problem with my 9c 2.0 . I swiched to fedral 115 fmj that day and had no more issues? Any thoughts? . Thanks for your help