Funny impression on brass after firing

windy

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Funny strange, not funny HaHa. This is out of an old commercial Mauser I just picked up chambered in 7x57. Any idea what is causing these marks? is it good, bad? Hopefully the attached pic works.
Thanks
Windy





Fn2C3aZ.jpg
 
Funny strange, not funny HaHa. This is out of an old commercial Mauser I just picked up chambered in 7x57. Any idea what is causing these marks? is it good, bad? Hopefully the attached pic works.
Thanks
Windy





Fn2C3aZ.jpg

It appears to be a fluted chamber. And the theory is for easier extraction. Fortunately Mauser style actions do not lack when it comes to primary extraction so you should not have any problems. If that was on a 700 chamber, good luck getting the bolt open.
Funny how things from long ago come back. There is a current rifle manufacturer who is doing this fluted chamber thing, as if it was brand new technology. I can't remember who it is but google will reveal who it is.
 
My 03 Springfield does that to brass - never knew what it was, never had any issues with it... but it is how I can tell my neck sized .30-06 for the 1903 from everything else :)
 
Would the chamber fluting make the bolt lift feel a bit more stuff than a non fluted chamber?

In theory I would think it should require less effort due to there being less chamber contact. However if you get any imperfections in most chambers they can be a real bugger to get the bolt to move as the brass embeds into the imperfections with the pressure exerted from within the casing. Most chambers want to look mirror like inside.
My only suggestion would be to keep your chamber as clean as possible.
 
Fluted chamber, my Aunt Fanny! The reamer chattered and the guy doing the chambering didn't notice.
 
Bill get your glasses on and look just ahead of the web, the flutes are extremely even where they end. It would be extremely unlikely to have the chatter not go right to the end of the chamber on a tapered wall cartridge.
This is exactly the same case marks made by several HK rifles. My G3 does exactly that to the casings. The "chatter" marks are far to precise.
Normally I would agree with you that it would be chatter but over the years there have been numerous manufacturers who have experimented with fluted chambers. Even waaaay back in the late 1800's early 1900's.
Google it.
 
I don't have to google it. The marks are from a high frequency chatter. If extraction is OK, the brass is reloadable as long as it is FL sized. H-K used fluted chambers as part of their system in their semi=auto rifles.I believe those chambers were produced via hammer forging. The flutes shown here were produced via operator error, flawed reamer geometry, or a combination of the two.
 
Bill, are you still gunsmithing? I just picked this rifle up a gun show and it's doing funny things to brass when firing. The proper thing would be to have a Smith check it out before I lose fingers and ruin a nice old gun.
Windy
 
I don't know how an individual could intentionally chamber a 'fluted' chamber using a reamer. I do realize that a 'chattered' chamber can occur due to faulty reamer, bad procedure or a bit of both.
 
This is out of an old commercial Mauser I just picked up chambered in 7x57.

I doubt that anybody would bother to flute a chamber on a commercial mauser, regardless of calibre. I agree with the reamer-chatter theory. Chambers were fluted on some semi-auto rifles as an aid to extraction, not something that has ever been an issue in a Mauser.
 
I have fired several guns with fluted chambers and none of the casings looked even remotely like the OPs picture...

I am in this camp.

I too remember H&K chamber-fluted brass, this isn't that.

Usually extraction-easing flutes are carbon fouled... not like these.

These look like a goofy chamber.

2 cents, right there.
 
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