Trim for uniformed length necked up 30-06 brass?
- Thread starter p5200
- Start date
at least check the brass length
when firing such large bottleneck cases, they lengthen regardless of how you size
things were explained to me like this:
- the primer detonates, tries to leave the case and pushes the case forward in the chamber as much as possible (the length of the headspace)
- the powder starts to burn and expands the case to the chamber size. Since the case is thinner towards the neck, in that area it will grab the chamber stronger than in the head webbing area that expands slower.
- then the pressure reaches max and the case moves back towards the bolt. The neck side holds tight on the chamber, the head side slides back stretching the brass just above the thick part of the head.
- this happens always regardless of how you size and it is directly related to the headspace.
edit: when neck sizing the headspace becomes minimal but the brass also flows a little (as in thins) because of the 60kPSI pressure. That thinning turns to lengthening as small as it is.
So, measure and decide for yourself.
when firing such large bottleneck cases, they lengthen regardless of how you size
things were explained to me like this:
- the primer detonates, tries to leave the case and pushes the case forward in the chamber as much as possible (the length of the headspace)
- the powder starts to burn and expands the case to the chamber size. Since the case is thinner towards the neck, in that area it will grab the chamber stronger than in the head webbing area that expands slower.
- then the pressure reaches max and the case moves back towards the bolt. The neck side holds tight on the chamber, the head side slides back stretching the brass just above the thick part of the head.
- this happens always regardless of how you size and it is directly related to the headspace.
edit: when neck sizing the headspace becomes minimal but the brass also flows a little (as in thins) because of the 60kPSI pressure. That thinning turns to lengthening as small as it is.
So, measure and decide for yourself.
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I didn't annual because I trimmed it, I do it to soften it for the next step, it going to be worked a lot in the resizing process. 8x57 you're turning a lot of sholder into neck. Its easier on the brass and dies, zero cracks.No need EVER to re -anneal brass because you trimmed it
What he said was he anneals before necking up 308 to .323 to prevent splits. Then, because necking up that much will obviously cause some work hardening, he anneals again after. It makes perfect sense.It’s not gonna get any softer unless you change the annealing code UNLESS your Bar B Qing it
I complely KNOW what he saying ! Thanks Thou !
What i said was annealingf it twice will NOT change the softness of the BRASS unless you anneal it longer and redder to further soften the brass ! which is not nessacary to do what hes doing !
You understand that working brass makes it harder again, right? So if you anneal and then neck up to another caliber, the brass is not the same as it was before necking up.
No it does NOT ! - thats BS ! shooting it makes it harder ! A few passes thru dies does not change brass hardness to any measurable degree at all !
So on this I will just agree to disagree ! Cheers !
Shooting works the brass by expanding it. Sizing it from 308 to 323 works the brass by expanding it. Same thing, no different. Cheers.
Completely DIFFERENT ! The brass does not get HOT just expanding it with lube thru a die - the work harding of it is NOTHING ! Cheers !
You haven't worked much with metal have you.
I could say the same about YOU ! And i have sized up and down a LOT of brass and annealed 1000 s of brass cartridges so dont start thinking so much Smarter Bud !
take a length of brass wire and bend it like this
now bend it backwards: it gets a W shape because the original bend hardened
resizing puts more stress on the case
Calm down, there's no reason to be upset.
My understanding is that cold working hardens brass by changing the crystalline structure at the atomic level. Now, I can't see atoms but my experiece is that sizing brass work hardens it and makes it more prone to failure..
I'm willing to learn. Do you have a source that says cold working brass does not harden it?
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So why do commercial ammunition manufacturers anneal brass several times through the process of making brass casings? They will anneal between forming stages even if no heat is applied. Cold worked metal still hardens.
