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Old June 15, 2019, 04:07 PM   #26
zeke
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Win brass is lighter and thinner, but do not believe it is weaker. Also believe the starting dia at the largest dia of the case body is about .0005 -.001 less in dia, and at the pressure ring is smaller yet.

From older brass and using stoney point 400 collar, but did not do a statistically relevant evaluation and did not subtract collar depth.

Win = 3.622
Fed = 3.618
Rem = 3.620

Have never stoned out a rifle chamber, but would be interesting to see if it increases chamber dia measurably. Would also be interesting to know make/model. 308 ar-10's can be picky, and have some with looser chambers, and some with tighter chambers that require sb dies. Some manufacturers may choose reliability over target purposes.

Am not in habit of using hunting loads in my ar's, but that is just an opinion.
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Old June 16, 2019, 08:19 AM   #27
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The bolt is supposed to be stripped before you try the go or no-go gauge. A good chamber should not allow a no-go gauge to close on it. If it does close (and the bolt is stripped), then the reamer went in too deep.

Second, it sound like the chamber wasn't polished after reaming.
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Old June 16, 2019, 09:07 AM   #28
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Again I am sure I am going to be the only one: I suggest you stop shooting ammo in that rifle. What the cases heads demonstrate is Catastrophic Failure. The 03 demonstrated failure at the extractor cut.
Catastrophic Failure: For a reloader their world evolves around the volume of a case; nothing else matters. I like cases with thick case heads, for most reloaders the case with a thick case head does not exist. I have crushed case heads with loads that should have caused catastrophic failure; instead the flash hole increased in diameter, the primer pocket increased in diameter, the case head increased in diameter from the cup above the web to the to the case head and the case stretched between the case head and case body nut the case head did not separate from the case body.

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Someone should suggest the OP take the rife apart to inspect components.
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Old June 16, 2019, 09:36 AM   #29
F. Guffey
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Quote:
Not sure what that's about but can only assume Guffey is talking off topic in a thread again . This thread has nothing to do with case volume or thin or thick walled cases as it relates to case volume . This is about my chamber and what it's doing to the brass and why .
I will try to type slower: It is not possible to punch hole in the case head with a chamber that has case body support. SO? there is something seriously wrong with your chamber and I suspect it is caused by the way the parts are assembled.

And then there was the 03; the 03 barrel has an extractor cut. I like the extractor cut because the extractor cut allows for more case head support but on thin case heads with heavy loads the extractor cut allows for the unsupported case head on the extractor cut side blow out.

Back to reloaders and their world evolving around case volume: I said I prefer cases with thick case heads when firing rifles in unknow condition. And then there were reloaders that claimed some 03 chambers had a lot of unsupported case head and they decided that was OK. I did not agree. My 03s have .090" case head protrusion from the bottom of the extractor cut to the case head meaning the 03 has more case head support than the 98 Mauser.

Difference between them and me? I know when the case blows out on the side of the case head the rifle has a very serious problem; I will not assume anyone knows and or understands, and then there are those that spend most of their time insisting the case has head space.

A more adult thing to do is to check the chamber for unsupported case head and then there is case head protrusion. My 98s have .110" + case head clearance. And then there is the case, most of my 8mm ammo if formed from 30/06 military cases. For those that believe the only thing a case has is volume my military cases have a case head thickness of .200" from the cup above the web to the case head.

And if I choose to thicken the case head by .060" I can do that but I would not think of firing a rifle without checking 'the gap between the end of the barrel and bolt face or as one of use refers to the gap as unsupported case head.

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Old June 16, 2019, 10:56 AM   #30
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The bolt is supposed to be stripped before you try the go or no-go gauge.
Agreed but at least half the AR type bolts I've stripped and that's several . I've bent or broke the ejector roll pin when reinstalling because I don't have the proper tool/s . Mainly something to hold the bolt firm and the ejector depressed at the same time while I use both my hands to tap out/in the roll pin .

The fact this was a brand new upper , I did not want it to look like I tinkered with the BCG just in case it had to go back and void my warranty or have any questions about what I did to cause any problem that may have come up . In this case that was a good choice . In most cases stripping a bolt is not that hard but the AR bolt needs 3 to 4 hands to do so .
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Old June 16, 2019, 01:37 PM   #31
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Agreed but at least half the AR type bolts I've stripped and that's several . I've bent or broke the ejector roll pin when reinstalling because I don't have the proper tool/s . Mainly something to hold the bolt firm and the ejector depressed at the same time while I use both my hands to tap out/in the roll pin .

The fact this was a brand new upper , I did not want it to look like I tinkered with the BCG just in case it had to go back and void my warranty or have any questions about what I did to cause any problem that may have come up . In this case that was a good choice . In most cases stripping a bolt is not that hard but the AR bolt needs 3 to 4 hands to do so .
It would seem if some of these reloaders put more time in finding an answer and less time talking tacky we would have solved this problem the first time it was asked as opposed to years later. I do not find it necessary to take the bolt apart I suspect I could trace my problem skills back to the fact I am not hard headed; and there is that thing with hot horse shoes, it does not take me long to look at them.

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Old June 16, 2019, 08:33 PM   #32
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Metal_god:
Quote:
Agreed but at least half the AR type bolts I've stripped and that's several . I've bent or broke the ejector roll pin when reinstalling because I don't have the proper tool/s . Mainly something to hold the bolt firm and the ejector depressed at the same time while I use both my hands to tap out/in the roll pin .

The fact this was a brand new upper , I did not want it to look like I tinkered with the BCG just in case it had to go back and void my warranty or have any questions about what I did to cause any problem that may have come up . In this case that was a good choice . In most cases stripping a bolt is not that hard but the AR bolt needs 3 to 4 hands to do so .
Perfectly understandable. Unless someone plans to do work on a pile of AR rifles it doesn't pay to buy or even make the tools to shop service the rifle. Working less the tools certain parts become a 3 hand or 4 hand operation and since most of us only have two hands our scope is limited less the tools.

I believe what is important in this thread is first your ejected cases should not look like those pictured additionally and more important is the numbers you got on the spent cases. The first symptom points to a poorly finished chamber, never polished. The second symptom points to excessive headspace and honestly with what you have I doubt measuring with a fully stripped bolt would make any difference.Based on your numbers and measurements the best thing you can do is arrange to return the rifle to manufacturer. Let them deal with it based on your complaints.

I figure when you plop down bucks for a new rifle you should expect a quality functioning rifle. My experience is that sometimes even a bad rifle makes its way out of a company known for good refiles and quality. Early on in the thread you confirmed what you pretty much already knew. I wouldn't screw with the gun or put any marks reflecting anything you did.

Ron
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Old June 17, 2019, 08:41 AM   #33
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I believe what is important in this thread is first your ejected cases should not look like those pictured additionally and more important is the numbers you got on the spent cases. The first symptom points to a poorly finished chamber, never polished. The second symptom points to excessive headspace and honestly with what you have I doubt measuring with a fully stripped bolt would make any difference. Based
It has never mad a difference to me but then there is Bart B; He can not get to case head to seat against the bolt face. And then there is case head separation and then the more serious catastrophic event, The rifle has to go to someone somewhere. If that person has a clue they will know hot high pressure metal cutting gas has escaped.

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Old June 17, 2019, 09:59 AM   #34
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Mr. Guffey:
As long as you quoted me, I do not see a connection between Bart B's comments in another thread and the main topic of discussion in this thread?

Quote:
It has never mad a difference to me but then there is Bart B; He can not get to case head to seat against the bolt face. And then there is case head separation and then the more serious catastrophic event, The rifle has to go to someone somewhere. If that person has a clue they will know hot high pressure metal cutting gas has escaped.
The image of the cases in this thread and only this thread reflect what appears to be a rough chamber on a new rifle. The case dimensions as measured by the end user would seem to indicate an over size chamber (a chamber exceeding SAAMI specifications) for a .308 Winchester chamber. The fired cases did not exhibit case head separation and there was no catastrophic event so while both did not happen they likely will eventually.

The symptoms make it clear there is a problem which should be addressed and since the rifle is new I see a return to the manufacturer as a viable solution to the problem(s).

What Bart B chooses to believe or disbelieve in another thread about a different topic is here nor there in this thread.

Ron
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Old June 17, 2019, 10:28 AM   #35
F. Guffey
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Quote:
The image of the cases in this thread and only this thread reflect what appears to be a rough chamber on a new rifle. The case dimensions as measured by the end user would seem to indicate an over size chamber (a chamber exceeding SAAMI specifications) for a .308 Winchester chamber. The fired cases did not exhibit case head separation and there was no catastrophic event so while both did not happen they likely will eventually.
Someone started the story about taking the bolt apart, someone started the story about the case having head space and reloader have been conditioned to say "I move the shoulder back" and "I bump". When I disagree they get wildly indignant.

Quote:
Unfortunately I shot all the Winchester ammo so I don't know what the case headspace started out at . Here are a couple pics of one of the pieces of Winchester brass that feels like there is a thinning of the wall at the web .
Reloadron, the picture of the case head illustrates a hole that is blown out, if the case head was supported there would be no 'hanging chads'. Again, reloaders do not consider case head thickness, for the reloader it is all about case volume; well there is one exception.

In the ops next picture he has a case head with a split case head . The OP is flirting with some dangerous stuff and he is needs help from someone that cares. I could form cases that would off set the distance from the shoulder of the chamber to the bolt face; problem, off setting the length of the chamber with a formed case will not correct case head protrusion/unsupported case head.

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Old June 17, 2019, 03:43 PM   #36
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OK, everyone has had their say.
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