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Posted: 4/20/2010 4:52:07 PM EST
Should I see any extractor pull marks on the muzzle side of the case rim? I see some that are deeper on xm193, but still there on bulk .223. I don't see anything on the breech side, no indenting, no rubbed or shiny spots.

This is on a 16" middy with standard buffer. No failures at all. I was just curious if the marks are normal or a result of overpressure. The extraction is at about 1:30, so I do believe I have some over pressure to begin with. I just ordered the spikes ST-T2 buffer to slow things down a bit, but don't have it in hand yet.

Are these cases still reloadable?
Link Posted: 4/20/2010 5:06:07 PM EST
Yes, extractor marks are normal.

You're probably seeing deeper marks on the 192 because it's probably loaded to higher pressures.
Link Posted: 4/20/2010 6:09:17 PM EST
Carbine gas systems are even worse. Some will rip the rim off. If it bothers you or you want to preserve and protect the brass for reloading there are several options that will reduce the force of extraction.

PRI and JP Rifles both make fine .750" adjustable gas taps which are easily installed. They'll allow you to dial down the amount of gas that goes to the bolt carrier.

Tubb's makes better flat recoil springs and a carrier weight system that will allow you to add weight incrementally which will delay the opening of the bolt and slow the process.

If you are running a collapsable stock you could try an H buffer or an H2 buffer. Don't overdo it, try the lighter one (H) first. If that doesn't work buy the H2.

If you handload, 52 or 53 grain match bullets driven buy 20.5 grains of H-4198 will be very accurate and not eject too hard. H-322 with those bullets loaded at 22.5 to 23.0 grains will be easy on the system too. Great accuracy from both powder bullet combinations.

Any of these options will get you headed in the direction you want to go.

Good Luck
Link Posted: 4/20/2010 6:49:07 PM EST
what brass, fed makes soft brass=deeper marks

still nothing to worry over
Link Posted: 4/20/2010 7:49:19 PM EST
Quoted:
what brass, fed makes soft brass=deeper marks

still nothing to worry over


lake city brass (head stamped "L C 0 9")

thanks for all the help guys!
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