[evolixsurf]

Could be from someone’s chamber but also I’ve sorted through some xm193bk bulk packs and found tons of lake city rounds/brass that I wouldn’t shoot. Deformations, cracks, etc. wouldn’t surprise me if that came from the factory like that.

 

[evolixsurf]

Here is the inside. Would using a resizing fix it and make this brass usable or not? View attachment 337594

It is a couple rounds.... throw them out.

 

[evolixsurf]

You should be able to look in the chambers and see. I would do that ASAP. I would never shoot or depend on a rifle with pitting in the chamber. The brass can expand and stick in those pits and have failure to eject and then your fucked. Never heard of a breach block. That sounds funny.

 

[evolixsurf]

Doubt that would have caused it in a chrome chamber. I bet it’s just bad brass but I would still clean and check all the chambers.