Same here.... In fact, this afternoon after lunch, I was shooting my old PSE bow in my back yard into the big field bag target. I too shoot with 20-30-40 pins with 125gr field tips for targets and 125 Thunderheads for hunting.

My bow shooting accuracy is like this:
20 yard pin = 1/2" groups, dead center bulleye.
30 yard pin = 1" - 1 1/2" groups into bullseye or rim of bullseye
40 yard pin = 1 1/2" groups to worse - being all over the target (still a bit unsteady and not 100% confident in shot placement at 40 yards).

Butch