When my dad first gave me my 686 I was concerned with excessive front to back play in the cylinder when it was open, now I'm concerned with the movement when its closed. I pulled the cylinder to the rear and measured the barrel to cylinder gap and it measured .009 I didnt pull it forward and measure but I know its atleast .004-.006 play (i'll check it tomorrow) anyways I was looking and found some kind of shims to correct endshake, is this want I need? Also would the shims work if I just wanted to tighten up the gap? I only use this gun for hunting and some paper punching, I usually only fire 25 to 50 round per range session and clean afterwards, If I do tighten it up is there anything to gain in performance? Sorry for all the questions, I know plenty in the rifle and cartridge world, but I'm a newbie in the revolver world. Thanks for the help, Kris