Yah on annealing with neck sizing- not every time. I probably do it every 3rd time which is excessive. If I'm going to full length size then I do it prior to sizing for sure though.
On the neck sizer- with the Hornady Match die, you order it in 308, then also order the 310 bushing for it. Then you just swap the bushing when going from one to the other. If I recall correctly, the neck sizer only comes in 308, not 310, so unless both barrels come out right for 308, you'll probably wind up needing to order the set regardless.
Here's the size chart for primer pockets. You can measure the depth with the depth bar (I think that's what it's called) on the end of your calipers.
https://ballistictools.com/articles/pri ... ameter.php
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