I believe that brass is made by Anatolia Cartridge Industry Co. LTD of Turkey.
I'm no metalurgist (paging Mr. Reihl) but I did stay at a Holiday Inn Express last night I'd venture a guess that the "step" in the brass creates a weak point between the thin and thick sections that fails, and that it's a by product of the mfg. process.
There are failures like this on other sites with this brass as well. While I doubt it's dangerous with a std. pressure 9mm load, I wouldn't be buying any of this stuff after I'd shot it up and certainly wouldn't reload any of it, you're just asking for trouble then.
Freedom Muntitions and LAX, amongst others, use this brass.
I read this thread just after ordering a second case of 115gr ball from Freedom Munitions. Today, I was picking up brass and noticed that my Freedom stuff all had visible primer flow/cratering, and all the brass had that 'step'. A friend of mine was shooting some newly imported Pobjeda steel-cased Bosnian 9mm today, and it had a similar (and if anything, more pronounced) 'step' in the case wall, but nowhere near as much cratering/flow. I didn't have any other brass 9 ball on hand to shoot alongside the Freedom, but the stuff does make me a bit nervous.
Well, I got a buddy of mine with a far better photography setup to take some shots of a fired case (as well as cases he shot from his G17), and sent them to Freedom. Thus far, they've been pretty receptive, offering to take it back for testing and either replace the ammo or refund my money, as I choose. Can't argue with their response to this point.
Doesn't surprise me.
Freedom has horrible quality control. I will get a shipment with 2,000 rounds with no issues. And the next shipment will have 2-3% that have some sort of issue. For example a couple of years ago during a Bob Vogel class, I was having a 1-2% failure to fire rate from a gun that had no consistent problems in the 10,000 rounds I have fired through it previously. When I got home I gauged the remaining portion of the ammo, 25% failed my case gauge, with about 1% being horrible failures. The most recent 3,000 rounds I had four really light loads (light enough that if it didn't hit a plate I checked for a squib), 3 of which failed to eject.
In all I've probably fired 10-12 case of Freedom Munitions. I will probably continue to shoot it as it is so cheap. But I use much better ammo as match ammo.
Just another data point for Freedom Munitions users. Last month(March 2015) I attended Op Sec Training's Practical Fundamentals class in San Antonio, TX. During the second day of the class, we had shooters experience three squib loads with two different lots Freedom 9mm. One gentleman had two squib loads from one lot of Freedom Re-manufactured 9mm. The two squibs were from different boxes of ammo within the same lot. The second gentleman had one squib with Freedom new manufacture 9mm.
I used to really like the stuff. Then i got afraid of it. After the big scare they had frequent seating depth issues and bullet set back issues. I stay away from them now. Sadly i trust Tula and Wolf more then FM.
The only issues I've seen with Tula and Wolf have been hard primers / failure to fire. I can live with that in practice ammo.
There were a couple shooters in the aforementioned PF class using Precision Delta re-manufactured 9mm. They reported no issues an highly recommended it.
I sent 350 rounds back to FM (300 from the case that I had issues with, and 50 from an up-until-then unopened case, just to have them check those too). They sent me a shipping label, and shipped me replacement ammo the same day that I shipped mine to them. It arrived today, and appears to be 350rds of remanufactured 115gr 9mm. Given the issues with their 'new' cases, I can't really complain. At least this way I get (hopefully) good factory cases to reload once I've shot this stuff. I'll check back with their CS rep and see if they have tested my new case. Either way, I doubt I'll order more. It just seems too risky to save $15 over Blazer Brass or something similar, especially if I have any issues reloading that odd brass.