Help understanding neck thickness and bushing dies

[barefooter56]

I was wondering about this exact point. My fire formed brass is 0.344 neck OD, and with a 0.337 bushing I would be compressing 7 thousandths. I thought I read on the Redding site that problems typically occur past 8 thou (end up with a narrower OD than the bushing is supposed to create), but I'm glad you told me otherwise.

Should I get a 0.340 and 0.337, using the 0.340 to step down from 0.344 before going to my final 0.337?

screamrider,
If it makes you more comfortable and confident in your reloading process. Do it.

FearNoWind,
The Hornady concentricity gauge is great to use on loaded ammo. Especially factory loaded ammo. It dosen't work with just a cartridge case. Also I believe I read in the instructions that IF the cartridge shows more than .003 run out on the bullet don't try to straighten it. It will loosen the bullet in the case neck . Great tool on factory ammo though. Also , WHEN YOU ARE MEASURING CONCENTRICITY ON A LOADED CARTRIDGE YOU WANT THE PROBE OF THE DIAL INDICATOR CONTACTING THE BULLET AS CLOSE TO THE CASE MOUTH /BULLET JUNCTION AS YOU CAN GET IT WITHOUT THE PROBE CONTACTING THE CASE MOUTH AS YOU SPIN THE CARTRIDGE.
TIP 2 : Make sure you PRELOAD the dial indicator at least .010-015 on the object you are checking and re-zero the face. This is done so the dial indicator probe does not lose contact with the object being measured causing an inaccurate result.