Take the casting and measure the neck diameter. Then subtract the diameter of your bullet (.224). Then divide the remainder by 2. This will give you the wall thickness of the neck. Now subtract .001" for neck expansion from the neck thickness. If your casting comes out to .248" - .224" (bullet diameter) = .024". Then divide by 2 = .012" neck wall thickness. Subtract .001" (for neck expansion on firing) = .011" neck wall thickness. A loaded round should be .246" in diameter. Your neck dies should have dies in the .244" area for proper neck tension for seating bullets, depending on how much spring back you get. After firing and resizing - neck run out is important at this point. If you are getting too much the case will chamber with some resistance. A possibility is that Wayne would be able to tell you what the neck diameter of the reamer was (maybe). I do not have a 22 PPC, but do have some experience with 222 Remington and you can order reamers with different neck diameters for it, depending on how tight you want the neck. I have heard of guys that turn necks to the point of not having to resize after firing. The neck expands just enough to release the bullet and then shrinks back down enough to hold the next bullet with out sizing. That is way too precise for me. Good Luck and Good Shooting.
