Brass weirdness

[laketrout59]

Anyone with ideas as to how and why this is happening to some used Lapua brass? One side looks just fine and yet the opposite side looks like designs you could do under an lsd trip. It's odd to start doing this for the first time. Suggestion
Thanks

 

[BRADMOTO]

You might have carbon ring, or build up in chamber if you haven't cleaned in a while. Causing uneven seal of the case neck area.

 

[laketrout59]

I guess I should have given more information. This is a 6.5prc, new barrel with only 16 shots. I have cleaned twice so far. Looked through bore scope, no carbon ring, no bore debris to see.

 

[RichCoyle]

Your load might be too light.

 

[Beluebow]

My uneducated guess is the smooth side is top side of the brass in the chamber....the funky side is the bottom laying in small layer of cleaning fluid.

 

[shoots4fun]

Anyone with ideas as to how and why this is happening to some used Lapua brass? One side looks just fine and yet the opposite side looks like designs you could do under an lsd trip. It's odd to start doing this for the first time. Suggestion
Thanks

I doubt it is a carbon ring issue. That would create pressure signs and hard to open bolt.
I also doubt that it is from too light a load because we generally see heavily sooted necks and shoulders with that.
While odd that is outwardly appears to be only on one side I believe I see the same Mottling on the "clean" side as well, just faintly.
You mention it being used Lapua brass. I ask if you had annealed it. Could be something showing up due to that or just an anomaly in the brass composition.

 

[WeiserBucks]

Your load might be too light.

This, soot from lack of pressure to seal properly.

 

[laketrout59]

Thanks for the thoughts. Not any liquid. Didn't think about low pressure. Shouldn't be but it is a thought. 57.2 grains n565. It is running slower than expected but it is a new 24"barrel.

 

[FireFlyFishing]

 

[Frank in the Laurels]

..put some more foot on the pedal...looks like gas caused gray..step it up a little and see if it persists..or you not trimming them back too much..reading the Mike correctly ?

 

[laketrout59]

Thanks. I can always add more powder. On grt as loaded it should be slightly more than 50200psi at 56.5?
Is that underpowered for fireforming this brass? 142smk tested between 56.4 and 57.0. N565

 

[laketrout59]

Edit should be 57.2 top charge

 

[243winxb]

Fired brass outside neck diameter larger then .301" ?
Chamber neck oversize or throat to long?

Seating bullets long, trying to get close to rifling?
Or the powder burn rate is to slow?

Just guessing.

Was brass neck turned?

Sierra Load Data