FWIW, I deal with pitch exactly as Jim Legg does. Whether it's a 26" SxS for grouse or a 32" O/U for targets, I cut the butt at 90 deg to the comb. In conjuction with 7/8" drop from nose to heel, I end up with a gun that makes full contact with the shoulder pocket and has little tendency to pivot in recoil. It's this pivoting that I'm trying to avoid as it results in muzzle flip and face slap and , in extreme cases with guns that have virtually no pitch, causes the butt to slip down between shots.
When you guys talk about "zero" pich, I'm not sure I understand how you measure that. What I would call "zero" pitch is a gun, typical of the oldies with excessive drop, that when stood on the floor and slid against the wall will allow the muzzle to touch the wall as the top of the receiever does. THAT'S the gun that won't stay in my shoulder pocket between shots, and that's what I want to correct by adding "some" pitch. Seems "degrees" of pitch would be most quantitative if you laid a straightedge from the heel across the top of the receiver and measured the angle the barrels deflected downward (or stood the gun on the floor and slid it against the wall), but measuring that angle would be a pain for me. Far easier to measure the distance of the barrels from the wall, but then you have to specify a certain distance from the floor. Using the muzzle as a reference would give variable results depending on the barrel length, action length and even the length of pull.
Personally, I don't consider gun fit prescription numbers worth the paper they're written on. I can supply an expensive blank to a duplicator and order a stock made with 1 & 3/8 x 2 & 1/8 drop, 3/8 cast off, and specify the butt be 90 degrees to the comb and KNOW I'll have enough wood to remove 50-100 thou from the comb during sight-in. When I'm done, the gun will pattern 50/50 as I like it.The final dimensions will vary 1/16" here and there from gun to gun, and the sight picture, due to rib configuration and possibly barrel regulation, will differ too.....but they all shoot to point of aim. Nowadays, rather than provide numbers, I prefer to make a perfect pattern stock using Bondo and rasps and give that to the duplicator. It has many advantages, including less chance for miscommunication.
The point to all my rambling , as it pertains to the original question, is that I have a "formula" that guarantees the "right" pitch for me regardless of the gun I'm stocking. I don't measure it in inches or degrees, except to say that I cut the butt 90 degrees to the comb. It's simple, it works every time and I've found no better way to guarantee the right pitch.
