Me and my oldlady went to the range this afternoon and we were there for about 45min and i noticed when i tried to cock the hammer to try some accuracy shots it wouldnt stay cocked so i could only fire in double action? We stopped shooting my revolver and we left because it was about time for me to go to work. But im wondering what would be the cause of this? She was shooting single action and double action before i even got to shoot it with no problems. I ran probaly 18 rounds in double action and then wouldnt cycle into single action.. The revolver was brand new when i bought it back in October 2011 and it has around 2500 rounds or so through it. Never had a problem with it before. Thanks.