.308 brass deformed

alloy · July 24, 2010, 03:53 PM

Anyone reloaded brass that came out of a similar chamber?
Any ideas what that chamber was part of?
Or is it a blank?

DiscoRacing · July 24, 2010, 03:54 PM

HMmmm .. new one on me... very interesting.. Nothing i have seen before.

alloy · July 24, 2010, 03:56 PM

It's a Lake City, '08 with the nato marking.

TXGunNut · July 24, 2010, 04:05 PM

My guess it was fired in an HK91 or similar rifle. Will reload just fine.

alloy · July 24, 2010, 04:10 PM

Just googled that rifle, mentions a fluted chamber.
Does sound about right.

William T. Watts · July 24, 2010, 05:58 PM

TXGunNut is correct, fluting is supposed to aid extraction for this type weapon. William

TXGunNut · July 24, 2010, 07:05 PM

HK94 does the same thing, not sure about the HK93.

FrankenMauser · July 24, 2010, 09:45 PM

Fired in a fluted chamber.

-Most likely an HK auto.

ISC · July 25, 2010, 12:38 AM

Yeah, CETMEs and HK 91s and their clones use the fluted chamber to allow extraction. Those rifles use a delayed blowback operating system that was originally designed for the 7.92x33 (8 kurz) round in the closing days of WWII. When it was scaled up to 7.62 NATO the German engineers (then working for Spain) had to use the fluted chamber to allow the brass to "float" out of the chamber. The flutes helped to reduce the pressure exerted by the case on the chamber walls by letting some of the gas flow between the case and the chamber wall, thus easing extraction.

It works, but makes for a filthy operating mechanism. Fortunately, those guns seem to operate fine when filthy, unlike the M16 which can get a little finicky when the combustion gases that are dumped in its direct gas impingement operating system are not cleaned after extended firing.

These guns also seem to be prone to sheared off rims and case heads when softer civilian .308 brass is used.

July 24, 2010, 03:54 PM	#2
DiscoRacing Senior Member Join Date: December 19, 2008 Location: milton, wv Posts: 3,640	HMmmm .. new one on me... very interesting.. Nothing i have seen before. __________________ Desert Eagle Alliance Group Launcher Extraordinaire ______ ----Get Busy Live'n.....Or....Get Busy Die'n......Red -------They call me Dr. Bob,,,, I have a PhD in S&W

July 24, 2010, 04:05 PM	#4
TXGunNut Senior Member Join Date: January 16, 2010 Location: If you have to ask... Posts: 2,860	My guess it was fired in an HK91 or similar rifle. Will reload just fine. __________________ Life Member NRA, TSRA Smokeless powder is a passing fad! -Steve Garbe I hate rude behavior in a man. I won't tolerate it. -Woodrow F. Call Lonesome Dove My favorite recipes start out with a handful of used wheelweights.

July 24, 2010, 07:05 PM	#7
TXGunNut Senior Member Join Date: January 16, 2010 Location: If you have to ask... Posts: 2,860	HK94 does the same thing, not sure about the HK93. __________________ Life Member NRA, TSRA Smokeless powder is a passing fad! -Steve Garbe I hate rude behavior in a man. I won't tolerate it. -Woodrow F. Call Lonesome Dove My favorite recipes start out with a handful of used wheelweights.

July 24, 2010, 09:45 PM	#8
FrankenMauser Senior Member Join Date: August 25, 2008 Location: In the valley above the plain Posts: 13,424	Fired in a fluted chamber. -Most likely an HK auto. __________________ Don't even try it. It's even worse than the internet would lead you to believe.

July 24, 2010, 05:58 PM	#6
William T. Watts Senior Member Join Date: January 20, 2010 Location: Central Arkansas Posts: 1,074	TXGunNut is correct, fluting is supposed to aid extraction for this type weapon. William

July 25, 2010, 12:38 AM	#9
ISC Junior member Join Date: August 5, 2007 Location: Florida Posts: 1,982	Yeah, CETMEs and HK 91s and their clones use the fluted chamber to allow extraction. Those rifles use a delayed blowback operating system that was originally designed for the 7.92x33 (8 kurz) round in the closing days of WWII. When it was scaled up to 7.62 NATO the German engineers (then working for Spain) had to use the fluted chamber to allow the brass to "float" out of the chamber. The flutes helped to reduce the pressure exerted by the case on the chamber walls by letting some of the gas flow between the case and the chamber wall, thus easing extraction. It works, but makes for a filthy operating mechanism. Fortunately, those guns seem to operate fine when filthy, unlike the M16 which can get a little finicky when the combustion gases that are dumped in its direct gas impingement operating system are not cleaned after extended firing. These guns also seem to be prone to sheared off rims and case heads when softer civilian .308 brass is used.