PWC
Member
Any type of a gizzy (comparator) can be used to measure headspace such as a spent 9 mm cartridge or a 30.06 cartridge. J[/QUOTE said:40 cal case, used as a comparator, comes real close to the SAMMI 30-06 datum line
Any type of a gizzy (comparator) can be used to measure headspace such as a spent 9 mm cartridge or a 30.06 cartridge. J[/QUOTE said:40 cal case, used as a comparator, comes real close to the SAMMI 30-06 datum line
I get that and agree. Going back to the very first post:The OP was asking if his Lee die FL resized cases could safely be used. To me this is a question about whether you can trust the out of the box resizing die. He compared a fired case w/ his resized case and found the headspace measurement (case head to 0.375" collar on comparitor for 30-06) difference was 0.018".
One person replied that the resized cases SHOULD NOT be used as the headspace was too short and could result in "Possible case head separations on firing. I had 223 brass separate with .014" shoulder set back." This suggests regardless of your chamber dimensions, resizing a case with a shoulder 0.014~0.018" shorter than your chamber is dangerous, and the cases should not be used for full charge reloads.
Is there a recommended "max undersized" headspace dimension that is considered unsafe? Is the min dimension the listed SAAMI cartridge (min) dimension or can the case be resized even smaller than SAAMI, but how much?
My sister bought me a bag of "once fired" 30.06 brass at a yard sale. It looked really good, so I decided to process it. So using my Lee full length sizing die, set as instructed, I resized the brass. (I set the die a little less than 1/4 turn down after the shell holder touched the die.) I figured I would full length size them, shoot them in my gun, then just neck size them afterwards.
Using my comparator, new rounds measure 2.44", and brass fired in my rifle measure 2.48". This used brass measured around 2.49 to 2.50 before I sized it. So imagine my surprise and consternation when I measured the brass after full length resizing to find it 2.30"!! (Yeah, I foolishly sized the whole batch before thinking to measure it while sizing.....)
Now I know what the future cure is; DON'T FOLLOW THE DIRECTIONS! Seriously, in the future I will set the die short, and then measure and set, measure and set, and measure and set until I get the die set somewhere reasonable.
But! What about this brass? Is it ruined? If fired, it will have a headspace of about .018". Too much to be safe? (If I do shoot it, I will anneal it before finishing loading them.) Also, I had read that the Lee full length sizer die was made to do a minimal sizing, so what happened here?
Thanks for any input,
Vettepilot555
Also remains the question of whether you all think that this brass would be safe to shoot once annealed. Once again, using my case comparator, which measures from shell base to the shoulder datum, new unfired brass measures 2.044". Brass fired in my gun measures 2.048". This brass I just sized with the Lee full length sizing die measures 2.030".
So a NEW round, fired in my gun, grows by .004" in length to fill the headspace. (From 2.044" out to 2.048".) If I fired the brass in question, at 2.030", it would have to grow by .018" to fill the headspace of my gun. Would this be safe? Would it weaken the brass such that further loading might be dangerous?
One person replied that the resized cases SHOULD NOT be used as the headspace was too short and could result in "Possible case head separations on firing. I had 223 brass separate with .014" shoulder set back." This suggests regardless of your chamber dimensions, resizing a case with a shoulder 0.014~0.018" shorter than your chamber is dangerous, and the cases should not be used for full charge reloads.
Is there a recommended "max undersized" headspace dimension that is considered unsafe? Is the min dimension the listed SAAMI cartridge (min) dimension or can the case be resized even smaller than SAAMI, but how much?