Any idea what caused this?

[jonzer77]

I was picking up my brass after shooting last weekend and I found these. They look like someone's reloads but I have never seen those grooves in the brass before. They are LC brass.

[twotacocombo]

Fluted chamber, probably from an HK or HK-clone rifle, like the C93.

[fal_762x51]

Fluted chamber from a roller locked action.

[Capybara]

Those rifles are the reloaders nemesis.

[Ubermcoupe]

That’s called HK brass

[ireload]

I agree with the above replies. Since I never dealt with fluted brass but has seen one, supposedly the brass can still be reloaded a couple of time before getting tossed as I have been told in the past.

[stilly]

That was prolly shot out of a PTR-91. Mine does the same thing. It throws the brass 27' to 2 on the clock and gives them zebra stripes before leaving the barrel.

I wish I had known about that before I bought it. Else I would have stuck with a FAL or some other semi .308... Maybe even that Mossberg MVP (bolt action)...

[RR.44]

Saw that years ago come out of an H&K 91, fluted chamber.

[J-cat]

They are reloadable. Anneal prior to sizing. The flutes will go away after a few firings.

[Beroen]

What is the point of a fluted chamber?

Just more cooling?

[dwtt]

The brass from my G-3 looks like that. Just reload it and don't use it for any other gun. I keep the brass from the G-3 separate from the other rifles.

[fal_762x51]

It floats the brass in the chamber to aid in extraction; no head case sepereation do to the violence of delayed blowback. More or less the idea.

[maxx03]

The brass is still reloadable. After a couple of firings the marks will iron out. Sometimes even after just tumbling them, the marks become un noticeable.

[Carcassonne]

The brass is still reloadable. After a couple of firings the marks will iron out. Sometimes even after just tumbling them, the marks become un noticeable.

+1

I have some brass from an HK 91, and after a few times, the flutes are barely noticeable.

It looks like it is from a HK-93



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