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Posted: 6/20/2009 5:41:33 PM EDT
| Is it inevitable that multiple loads of a bottleneck catridge full length sized and fired in a semi auto is going to show signs of incipient case head separation? |
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I resize my cases to just right at factory specs so they feed in my AR10 but I also shoot a Rem 700 which I can just neck size for.
I had two cases fail recently when testing loads in the AR10. I have been doing the paperclip test and I do feel varying levels of the head starting to thin out on more than 3/4 of my 100 round sample. I need to do some more testing which I am assuming will show more loads for the bolt gun even when full length sizing compared to the AR10 which has alittle more headspace than necessary. Of course these are the initial 100 cases that I got from a buddy who had bough 100 rounds of Georgia Arms factory reloads so I am skeptical of the cases anyway since they were already loaded once and I do not know what weapon they were fired in previously. It's still interesting to see the insides of the cases and how they thin out. Do you guys toss the brass once you feel any separation or when it starts getting bad? |
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Quoted:
I resize my cases to just right at factory specs so they feed in my AR10 but I also shoot a Rem 700 which I can just neck size for. I had two cases fail recently when testing loads in the AR10. I have been doing the paperclip test and I do feel varying levels of the head starting to thin out on more than 3/4 of my 100 round sample. I need to do some more testing which I am assuming will show more loads for the bolt gun even when full length sizing compared to the AR10 which has alittle more headspace than necessary. Of course these are the initial 100 cases that I got from a buddy who had bough 100 rounds of Georgia Arms factory reloads so I am skeptical of the cases anyway since they were already loaded once and I do not know what weapon they were fired in previously. It's still interesting to see the insides of the cases and how they thin out. Do you guys toss the brass once you feel any separation or when it starts getting bad? Are you keeping your neck sized 700 Rem brass and your AR10 brass in separate piles? Do you have a case gauge? |
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Quoted:
...I had two cases fail recently when testing loads in the AR10. I have been doing the paperclip test and I do feel varying levels of the head starting to thin out on more than 3/4 of my 100 round sample. ...Do you guys toss the brass once you feel any separation or when it starts getting bad? In my view, any noticeable thinning of the case head means that case shouldn’t be reused. I’d toss that entire lot. I’d say it’s inevitable that any bottleneck case is going die from split necks, loose primer pockets, or case head separation if you reload it enough times. (Technically this is no doubt true with any case, though I’ve got some .38 Spl brass that I load lightly and just about refuses to die.) Full length sizing certainly speeds up the case head separation issue. Other things such as how hot you load the rounds also can make a difference. Ideally, if you start with a batch of new brass and treat it all the same, you can figure out how many loads you can reliably get out of it before any issues arise. And then just toss all that brass when you get to that point, if not a bit before. Brass doesn’t last forever. |
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I find necks splitting or cases cracking lengthwise more often then signs of case head separation. You should get anywhere from 5-20 loads per case depending on cartridge, how hot it is loaded, chamber size, neck versus full length sizing, etc. Eventually all brass dies. Until then it is all "free" after the first load! Handgun brass lasts much longer than most rifle brass (shorter, less pressure). |
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Quoted: Only if you don't loose it first.  That is the only sad means of brass going out of service. Worn out brass is a good thing, well earned end of life. Of course, we brass picker-uppers (aka, "brass whores" according to envious non-reloaders) will crawl on our bellies with lights, and scour a site many, many times before we give up on the last piece of brass not accounted for. I know all the brass I have lost over the last 20 years will easily fit into a sandwich size Ziploc. Recovered brass would fill several 5 gal buckets.  |
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Quoted:
Are you keeping your neck sized 700 Rem brass and your AR10 brass in separate piles? Do you have a case gauge? Yes, I was keeping the brass separate but decided to just FL resize everything from now on. I have a Dillon case gauge and the shoulder is just bumped back enough to be in spec. |
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I'd say that it would depend on your rifle's chamber and action and your re-loading methods/practices and load data that you're using With some rifles (such as the M1A)............well, brass doesn't last long. I try to retire my brass before I get a head separation. So, that means I can usually get 3 re-loads with US military once fired brass..........a 4th would be pushing it. Brass in an AR will usually last longer. And, brass from a bolt action will usually last even longer. Then, we haven't touched on the annealing, for the case neck split issue. Aloha, Mark |
| In the Dec Handloader Magazine article on loading accurate .308 rounds, the author intentionally ran life tests on several brass case brands. He put in .005 headspace clearance by full sizing each reload, bumping the shoulder back the same each time the case cycled back through. He ran the same bullet wt and powder load through a bolt rifle and took all cases to final destruction (case separation). The results of these life tests were very interesting. |
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