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Therefore, it is possible to have a CHAMBER that is on the BIG end on one spec and SMALL end on another spec.
The standard dies made by die makers are INTENDED to (when set to cam over) reduce the case no matter how thin or thick that brass wall may be (you should be thinking of the concept of tolerance stacking right now) to fit into the SMALLEST chamber in ALL measurements.
So, when we add up all the measurements, all the variables, all the differences in brass lots, and toss in a dose of shellholder, brass aging and springiness, it is no wonder that you may see that your one, two, three, four times fired brass has yet to reach its full "length" from base to shoulder, given that you are cold swaging it every time after firing with an adjustable (read changeable) die.
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EXCELLENT explanation that inexperienced reloaders would do well to heed.
Finding harmony between factory reloading dies and chamber/reamer specs, when dealing with various lots/brands of brass, is not always an easy proposition...