John given the options you have provided and the 30 yards max distance I would opt for the 6's. For years the argument around here was whether to use 4's or 6's, I just split the difference and have always used 5's. That decision was made considering the fact that at the time I was shooting 3" and 3 1/2" loads with up to 2 ounces of shot and shooting some distance, or hoping to. Now that I am using my Parkers on turkeys and limiting the shots to 30 yards or so I am more in favor of the 6's for the pattern density as I am using RST ammo with 1 1/8 ounce of shot. RST offers what they refer to as a Pheasant load which is 1 1/4 ounces of 6's at 1200 FPS. I am wanting to pattern that one some day. I am with Reggie on your ammo in that I would not shoot those in my Parker, others will but I will pass. You should have your guns barrels evaluated by a competent gunsmith to determine their integrity also. Forget the 2's unless you want to put one of those in the second barrel just in case a coy dog wanders by