My guess is if it's what I was talking about where the hammer rides ageist is that they polished it making is much smoother but maybe wider. always put a drop of oil on that part or use a dap of Seal 1 I found that to be much slicker.. Frog lube is good too.. Seal 1 or Frog lube will get down into the pours of the metal like oil can't.. Also don't use force when installing a loaded mag in the gun with a open slide.. this will widen the lips on the mag in a short time and cause feed issues.. George