I just bought a new M&P M2.O, cleaned it lubed it per manual and tried it out 115 grain fmj, many failure to feed issues, and sometimes the action would not stay open after last shot. noticed the mags don't fit tight in the gun, they have about a 1/16 play when inserted in gun. only one type of ammo today will try more tomorrow has me worried about reliability of this gun, my others all feed anything. any ideas besides just breakin time? thanks.