Nonsensical Headspace Measurements on 223rem cases...??

In my early days, 1979 , with no comparator or cartridge gauge, the Dillon shell plate gave me .014" shoulder set back and case separations in my M16A1 carbine.

That is interesting. I didn't think about there being that much variance in the thickness of the shell plate and I bet that's another factor in the variance I get, not just slop in the machine itself. I also adjusted the bullet seating die down to the same amount of touch and I size all my brass at once without rotating the shell plate. Doing this I get decent tolerance.

But now thinking about all that maybe I could adjust my die up to bump the shoulder less, and not rotate the shell plate and get acceptable variance (no more than +-.003)
 
Alright. All of this is for non-precision stuff anyway, so the variances don't really bother me that much. Just wanted to make sure I wasn't overworking my brass or putting myself at risk of head separation.

twadsw01

You asked the same question at http://www.m4carbine.net/forumdisplay.php?72-Reloading-amp-Ammunition and got very good answers. markm runs a AR15 shooting school and has reloaded vast amounts of .223/5.56 ammunition. And I would guess that markm has reloaded more ammunition for the AR15 type rifles than everyone reloading total here.

You are over thinking your reloading problem and need to spend more time reading the front part of the reloading manuals. I'm 67 and have been reloading for over 47 years and never had a single case head separation.

markm stated he does not use a Hornady cartridge case headspace gauge and just used a standard drop in case gauge. And markm has loaded more .223/5.56 amunition than you will ever load in your lifetime.

"KISS" = Keep it Simple Stupid.............and stop over thinking a simple resizing step. A resizing die is adjustable up and down and you can set the die up for the correct shoulder bump with a simple case gauge like markm stated.
 
there were 5 people that replied to his original post, including you. your reply, was regarding his brass not his chamber would indicate you understood what he was asking/saying as well.
 
How would full-length sizing a case increase the headspace measurement on a .223 case, and charging/seating/crimping decrease the headspace measurement??

Because a case grows when full length resized (Newton's third law) and then the case shoulder is pushed back down by the shoulder of the die. This is why resizing dies have threads so the die can be adjusted up and down for the correct amount of shoulder bump.

And below you want the case shoulder .003 to .006 below the red dotted line after full length resizing on a semi-auto.

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And if the case is shorter after bullet seating, it could be seating force or the crimp making it shorter.
(it that third law thing again)

Try lubing the inside of the case neck with powdered graphite to ease seating force. And crimp in a separate operation and see which step is making the case shorter.

So stop over thinking and over engineering a simple sizing operation.

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there were 5 people that replied to his original post, including you. your reply, was regarding his brass not his chamber would indicate you understood what he was asking/saying as well.

Thank u for ur concern.

Not from the onset, but eventually I decided his incorrect terminology needed help.

Do u really see a problem w that?

No need to answer. eom
 
Using Lee seating and crimp dies, but a Hornady sizing die. Will definitely try to get lube in the neck next time.

Thanks, all, for the replies. Yes I've posted this several places to try and gain as many responses as quickly as possible...and with good success!
 
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