Shoulder bump

Don't bump your shoulders unless they've grown to fit your chamber. If you start short and they don't grow enough to be tight after a firing then why would you bump them?
To keep them consistent every shot, and know they will feed every shot. It's .002". Less than a human hair. Brass isn't being ruined by sizing that amount each time.
 
Every time, anneal, FL body size and mandrel for neck tension.
Don't bump your shoulders unless they've grown to fit your chamber. If you start short and they don't grow enough to be tight after a firing then why would you bump them?
If they start that short and are not expanding into your chamber to be tight you will have head separation problems sooner than later. Something is wrong with your chamber specs or the brass to begin with. Even if you bump .005 or .006 you should get a tight bolt close on a fired case, if you're not I would be concerned.
 
I do it every time but that's only if the shoulder moved enough to be bumped back. I measure with a headspace comparator on my new brass, record that number and then again after I deprime, but BEFORE, resizing fired brass. If it didn't grow, then I just set my die to leave it as-is. I adjust as necessary on future firings based on how much it grew and if a fired piece won't chamber or is difficult to chamber.
 
Once I set my die to where I want it bumped back I don't change anything unless I lose accuracy. Just went out Saturday with my 308 pushing 2975FPS and it's still on with 2 shots. That's all I should need.
 

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If you're not running hot and extraction is easy don't worry about it if you don't want to. As you can see people have a difference of opinion on this old and tired argument. I'm seeing a lot of tier 1 shooting advice that the average reloader is going to get lost in all the other noise in the process.
 
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