Got checking some of my other Parkers. I have a lifter 12ga built in 1875 with 2 5/8 chambers and no step. But the barrels do tighten very very quickly. Maybe someone at some time ground the step out. My 10 giving me so much trouble was built in 1879 with the step at 2 5/8. A 12ga top lever hammergun built in 1908 has a step at 2 7/8. I find the last one interesting with a step at 2 7/8.

Paul, I'm wishing I still had my problem 10ga to check further, but I did find my notes of that gun. It was an Underlifter, #6128, made in 1875, 0 grade, 30" Twist, 2 5/8" chamber with step, 9 pound, 2 frame, choked IM both barrels.

Dave

Been in a slump lately - about 10 birds down. So I shot my #4402 lifter 12ga with 30" twist barrels and straight grip. Shot better - that gun always seemed to fit, feel, and handle so nice. I had redone the wood and Brad redid the barrels. It just may be my new favirote gun.