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  #11  
Old 08-23-2018, 12:30 PM
ceresco ceresco is online now
 
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The image is the exact failure I am referring to. The 1917 has long headspace, but I had used it for several months with no problems other than the expected elongation of fired cases. The failures occurred from a batch loaded specifically for CP GSV matches, different only in that I FL sized them to minimum (base to shoulder) dimension to prevent any problems due to tight chambers. No failures in the M1 or the two1903 rifles--only the 1917. I had a couple splits at home while zeroing the 17, then several during the match. Consequences were flashback around the bolt and possible eye trauma. After the third failure during the match, I stopped shooting. Wearing regular glasses was not enough and too many failures to be random events. I have found no explanation to this date nor experienced any such failures in my mixed pool of HXP brass. Remains a mystery.... The 17 will not be used until I find a longer bolt to shorten the HS some, for what that is worth and I will be wearing goggles when I get back to it. Good Shooting. .?
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  #12  
Old 08-23-2018, 12:56 PM
wghenderson wghenderson is offline
 
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The AR 10 was headspaced at 1.631. I do not think it would be the problem in this case.
Just looking through my old brass I found two more with the same failure from the same batch that was fired in a CMP .308 Special. There is no apparent damage. I do not know what the headspace is on that rifle.

W.G. Henderson
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  #13  
Old 08-23-2018, 03:00 PM
zippysrifle zippysrifle is offline
 
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Mine looked like the photo posted by Shomway. I still have 2 on the shelf above my reloading bench as a reminder.
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  #14  
Old 08-23-2018, 05:32 PM
docsparks docsparks is offline
 
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Default That is my case.

As it was relayed to me, It was outsourced LC cases that were used in machine guns.

As suggested, I pulled all the rounds and reused the projectiles, scrapped the brass.

I bottled the powder for the future use or not.

Having had the experience, I personally would not shoot it. They are not all bad but how do you know.

Doc
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  #15  
Old 08-23-2018, 05:49 PM
GGaskill GGaskill is offline
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It would be interesting to see one of those cases sectioned to see the actual split path. My guess is that the large amount of resizing that machine gun fired brass needs would have work hardened the case head to excessive hardness unless it actually caused a split. Probably should section a few that were fired but did not fail to see what condition they are in.
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  #16  
Old 08-24-2018, 10:00 AM
rickgman rickgman is online now
 
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Quote:
Originally Posted by wghenderson View Post
The AR 10 was headspaced at 1.631. I do not think it would be the problem in this case.
Just looking through my old brass I found two more with the same failure from the same batch that was fired in a CMP .308 Special. There is no apparent damage. I do not know what the headspace is on that rifle.

W.G. Henderson
W.G., Did you happen to dimensionally check any of the unfired ammo - specifically the shoulder to the base dimension? I wonder if some of the shoulders were pushed back too far leading to effectively a short cartridge which would have the same effect as too much rifle headspace. Just a thought.
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  #17  
Old 08-24-2018, 11:30 AM
wghenderson wghenderson is offline
 
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Unfortunately, the few remaining the cartridges were pulled and reloaded with light bullets and reduced powder loads and shot in a bolt rifle with no failures and then discarded. IF I recall most of the failures were head stamped "LR" which I thought were to used in bolt sniper rifles. If this is true, it is likely a manufacturing defect.

W.G Henderson
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  #18  
Old 08-26-2018, 09:13 AM
togor togor is offline
 
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Would be curious if anyone put unfired Atomic ammo through a case gauge to see if the brass ran short coming out of the resizing process. Most likely a QC problem in propellant.

I've reloaded 7.62 LC from MGs without incident, as have many others. I do anneal prior to the resizing for rifle use, but I've checked and see no telltale signs of case separation in the cases I've examined.
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  #19  
Old 08-29-2018, 02:34 AM
GGaskill GGaskill is offline
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Togor,


Were your cases "reconditioned"?
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  #20  
Old 08-29-2018, 04:46 AM
nf1e nf1e is online now
 
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I have shot a ton of this stuff but after the initial warnings I drop every cartridge into a Sheridan cartridge guage. Pass/fail. If it drops in and slides back out it is good to go.
If it hangs up on the web like this one it gets pulled and reloaded in better brass. I have found that about 25 to 30% do not pass the test. They are hanging up on the web area, not the extraction rim. With over 2K fired I haven't had any mishaps after guaging. At least they came in nice Plano boxes.

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