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ColColt
09-30-2011, 09:05 PM
Any ideas what's causing these weird markings on this brass...especially under "Auto"? I don't see anything out of the ordinary on the breech face.

http://i180.photobucket.com/albums/x220/ColColt/Misc%20Stuff/_DEF3783a.jpg
SciFiJim
10-01-2011, 12:35 AM
I don't know the right name for it, but it is caused by the brass hitting the part of the frame on the left side of the chamber that causes the brass to pivot around the extractor and be ejected.
9.3X62AL
10-01-2011, 10:10 AM
The mark at the bottom appears to be an ejector strike, which would be normal. The burnished area at 12 o'clock to 4 o'clock might be evidence of early unlocking. Is the pistol retro-fitted with a lighter recoil spring? Perhaps a new "stock tension" recoil spring would be in order, or a reduction in load pressure and/or its dwell duration may be indicated. Has anyone changed out the toggle link (in a 1911A1), or replaced a barrel in the pistol? Absence of flattened primer radius edges in calibers of this pressure level is no promise of safe pressures.
Mk42gunner
10-01-2011, 04:34 PM
I agree with Al. It looks like early unlocking, the marks on the casae and primer being caused by the barrel dropping before pressure is released. The ejector mark is quite prominent also.

What was the load and how did it shoot?

Robert
ColColt
10-01-2011, 09:12 PM
I found out what it was. If you look at the slide with the barrel pointed toward you and opposite from the extractor, there is a raised section the exact size of that mark on the brass. I took a toothpick and ran it across the full width of the breech face or recoil shield as some call it, slowly and moving from the side the extractor is on toward the opposite side, there was a distinct step you could feel at the far side. That step is what's causing the indentation in the brass.

I used a needle file, hard stones and finally a bit of Mother's Mag polish on it and got it down pretty good. I won't know if further work is required until next range session. It wouldn't matter if you don't reload but being a reloader I can't live with that so I may have to go over it yet once more depending on my finding next week.

the load didn't matter as it did that with all of them from the few factory loads I tried to 230 gr FMJ loads and also with 200 gr LSWC's.
MtGun44
10-01-2011, 10:04 PM
As said, the bottom mark is a normal ejector mark. I have some brass with the headstamp
literally beaten off of the case, because it has had so many ejector hits.

Bill
ColColt
10-01-2011, 10:42 PM
As said, the bottom mark is a normal ejector mark. I have some brass with the headstamp
literally beaten off of the case, because it has had so many ejector hits.

Bill

It's from a machining artifact from cutting the breech face and created a step. That's what caused the marking on the brass. I could see and feel it while dragging a toothpick over it. The ejector is one of the extended varities and wouldn't be that long.
HamGunner
10-03-2011, 10:29 PM
Are you using a slow burning powder?
MtGun44
10-04-2011, 12:34 AM
OK, a regular ejector will make a mark very much like that.

Bill
ColColt
10-04-2011, 06:54 PM
Are you using a slow burning powder?

No, HS-6 is the only one some may consider slow but the others(231 and Universal) gave the same markings.


OK, a regular ejector will make a mark very much like that.

Very true but, usually there's not as long as this one. that's what tipped me off it wasn't that. Looking at the extended ejector it's not half that long where it hits the rim on this one. I hope to be able to get to the range Friday to test what I've done.