destrux
02-24-2015, 08:40 PM
I was sorting some .40S&W brass the other night and I noticed there were cracks in a perfect ring shape inside the brass near where the case wall meets the base. I will post pictures when I get home later to clarify the location, but they were more on the base than on the walls.
I noticed them on almost all the brass brands I had, but the exact location of the crack ring varied. I'd say about half the once fired (it's mine, I know it's once fired) brass I was sorting was cracked. None of it was fired from a Glock or any other unsupported chamber, all of it went through my S&W M&P and my HK P2000SK which fully support the case.
I wasn't sure if it was just the way the brass looks after the cases are formed at the factory or not, so I sectioned a few pieces to see if they were actually cracks and how deep they went.
The RP and Winchester brass had a ring that was smaller and directly above the inside of the extractor groove. The crack didn't seem to be deep enough to even see it once the brass was sectioned.
The Fiocchi and PPU brass I sectioned on the other hand... they had a ring that was directly on the junction of the base and the wall, and the crack was visible after sectioning. You could see that it extended about halfway through the case head toward the outside edge of the extractor groove. I think that will likely cause a case head separation won't it? It was on every single piece of once fired Fiocchi (GFL) and PPU brass I had.
Oh and I also checked my 9mm and .45 ACP brass and found the same cracks in them. So it doesn't appear to be a .40S&W thing.
I will update this thread with some pictures when I get home in a bit, but I wanted to type this out before I forgot.
So is this something to look for and worry about or is it normal and I can ignore it and just use the brass till it dies of the usual neck splits?
I noticed them on almost all the brass brands I had, but the exact location of the crack ring varied. I'd say about half the once fired (it's mine, I know it's once fired) brass I was sorting was cracked. None of it was fired from a Glock or any other unsupported chamber, all of it went through my S&W M&P and my HK P2000SK which fully support the case.
I wasn't sure if it was just the way the brass looks after the cases are formed at the factory or not, so I sectioned a few pieces to see if they were actually cracks and how deep they went.
The RP and Winchester brass had a ring that was smaller and directly above the inside of the extractor groove. The crack didn't seem to be deep enough to even see it once the brass was sectioned.
The Fiocchi and PPU brass I sectioned on the other hand... they had a ring that was directly on the junction of the base and the wall, and the crack was visible after sectioning. You could see that it extended about halfway through the case head toward the outside edge of the extractor groove. I think that will likely cause a case head separation won't it? It was on every single piece of once fired Fiocchi (GFL) and PPU brass I had.
Oh and I also checked my 9mm and .45 ACP brass and found the same cracks in them. So it doesn't appear to be a .40S&W thing.
I will update this thread with some pictures when I get home in a bit, but I wanted to type this out before I forgot.
So is this something to look for and worry about or is it normal and I can ignore it and just use the brass till it dies of the usual neck splits?