If you want to get rid of the ping when you shoot , just change out the Buffer Spring to a Chrome Silicon Spring from Tubbs , works better than going to a heavier buffer in my experience
The ping annoys some folks, but for folks that shoot a LOT, and understand the mental part of the game, IF you can hear the ping, you are not performing the shot process correctly. I used to laugh when I heard that and then realized... wow they were right... if i oculd hear it ping, I wasn't mentally doing what I needed to.
The other cure is simply wipe the spring with grease a bit...
