Re: new to building rifles and need help
Very nice write up Chad, very detailed.
One thing an old BR friend has taught me - use the stub of barrel you cut off, to make a chamber gauge for your brass. It does not have to be as long as the brass, unless it is a belted mag, headspaced on the belt. To make it:
Face off both ends of the stub, keeps it pretty.
Sink your reamer into the stub, as deep as possible, without allowing the bullet end of the brass to exit the stub. You want the head end of the brass out of the stub when finished.
Next, shoot the rifle, with a new batch of brass. Take the brass as removed, and measure the projection of the head end from the stub. It is easiest to do that with calipers across the head end and the opposite side of the stub. Write that number down.
Next, resize the brass, setting up the die, such that you only move the shoulder back .001". You use the guage you just made to measure that setback. Works like a champ every time, extends brass life a lot. It is not unusual for BR guys to use the same 10-20 pieces of Lapua brass for several HUNDRED reloads, by minimizing the shoulder set back. I have shot an entire weekend match ( 100 rounds, plus warmups and sighters ) with ten rounds of brass, and not had to trim case length.
Not exactly on topic, but if you are learning to chamber, it's good info.