Interesting 9MM brass

[Walkalong]

I picked up some interesting brass at the range a couple of weeks ago. It is Blazer Brass, although I don't think that has anything to do with it. I have picked up plenty of Blazer Brass that does not look like this brass. The first one I saw laying there I thought was a .357 Sig because it looked bottle necked. The brass is a tiny bit bulged just above the web, which is not unusual, but it has a ring all the way around about 1/4" from the case mouth. It looks partially sized, but was obviously just fired and left laying there. The was a Blazer box was in the trash can at the pit, so I think it is once fired. It looks like it. The primers look completely normal. I picked up quite a few of them that look just like the ones in the pics.

Strange. Chamber issues? Anybody see this before?

 

[rcmodel]

Any chance it is the remains of a case cannulure to prevent bullet set-back?

I can't tell if there is actually any bottle-neck, or if it's just normal case bulge and a cannulure ring ironed out.

Never seen a real live Blaser brass 9mm in real life???

rc

 

[ambidextrous1]

Could it be that they were fired in a firearm chambered for .40 S&W?

 

[dakotasin]

interesting... guess it wouldn't concern me much until after it went thru the sizing and flaring dies, and if it didn't look right, i'd pitch it.

i haven't ever seen 9mm blaser brass, either.

 

[Walkalong]

Not a cannelure, and the first 1/4" is smaller in diameter, just like it was partially sized.

.379 to .382 there.

.391 to .392 in the middle.

.3855 at the web.

Not fired in a .40. I have seen those. Much worse.

 

[Marlin 45 carbine]

or 9mm Makarov?

 

[Walkalong]

Here it is after sizing. They all fit the gauge and would drop out on their own.

 

[NuJudge]

Maybe just an ugly chambering job?

CDD

 

[helg]

Some guns are designed with loose chambering - for reliable feeding in dirty conditions. The glocks are. This ends up in having bulged firing brass like you have shown. The bulged brass is harder to size, but it still can be reloaded.

When firing reloads through the loose barrel, you see that brass is overworked and cracked sooner. Also light 'target' loads through the loose barrel give dirty brass and a lot of smoke, as the brass does not seal properly.

 

[depoloni]

Just a sloppy chamber. I watched a guy create 200 of these, except with Federal American Eagle 9mm ammo, with a Hi-Point 9mm carbine at my local "brass herding spot" just the other day.

For some reason, either barrel/receiver fit (?) or sloppy chambering, it does that. Never had a problem re-sizing and using them in my own pistols, regardless of headstamp. Can't tell you what actually makes some firearms do that, but the H-P was the first (p.o.s. admittedly) I've seen do it in front of me with my own eyes. Picked up plenty like that over the last couple years though.

 

[Walkalong]

This ends up in having bulged firing brass like you have shown.

Look closer. The bulged brass you are talking about is a different puppy.

I watched a guy create 200 of these

Interesting. So I guess the consensus is a sloppily machined chamber. Maybe a little chatter going on with a reamer on the way out.

 

[helg]

Look closer. The bulged brass you are talking about is a different puppy.

40SW glocks is a different story. These glocks do not support round completely at the bottom for the sake of reliable feeding - and this gives so-called "glocked brass", which is bulged only on one side. 9mm glocks support round from all sides, but very loose. This gives symmetrically bulged brass.

 

[D. Manley]

40SW glocks is a different story. These glocks do not support round completely at the bottom for the sake of reliable feeding - and this gives so-called "glocked brass", which is bulged only on one side. 9mm glocks support round from all sides, but very loose. This gives symmetrically bulged brass

.

I think helg may have it with one caveat. While some early edition Glocks were lacking support at the 6 O'Clock position (feed ramp) particularly, the .40 calibers, this is no longer the case. They are now quite well supported there and pretty much the equal of any other combat pistol.

That said, the internal chamber dimensions remain quite "generous" on the current .40's. My G-35 produces spent rounds precisely like those in your pictures...a gentle, concentric bulge in the center part of the case with the mouth and case head area appearing fairly "normal". This bulge will be present in the .40's even with, very mild Minor PF loads...it's the nature of the beast. I have 4 Glock 9MM's and I've seen no such bulge in those even with, hot rounds. Come to think of it, I've not seen the same thing in any 9MM brass...only, .40.

FWIW, my similar .40 rounds resize normally and shoot just fine with no ill effects. If the brass life is shortened by the bit of extra expansion, its not by a quantifiable amount.

 

[ReloaderFred]

Walkalong,

There is a pistol that has a two piece chamber, but for the life of me, I can't remember which one it is at the moment. I've also been picking up brass exactly like yours at our range. It's the chamber that causes it and has nothing to do with the brass. I've been getting all brands of brass with the same pattern.

I remember reading somewhere about the two piece chamber several years ago. The back of the chamber, which I believe is part of the frame, is reamed, and then the barrel is screwed into the half chamber and forms the forward portion of the chamber, leade and bore.

I'm doing this from memory, so don't hold me to the the exact description, but that's what I remember the makeup being. I just wish I could remember what brand of firearm it was.........

Hope this helps.

Fred

 

[Walkalong]

so-called "glocked brass", which is bulged only on one side. 9mm glocks support round from all sides, but very loose. This gives symmetrically bulged brass.

OK. I am missing something. Does it give the "sized" looking front part as in the pics. The "Glocked" brass I have seen in 9MM only has a bit of a bulge in the rear above the web.

 

[RyanM]

Almost definitely a loose chamber. Looks like it's bored cylindrical up until the last 1/4", where it tapers down to index on the rim.

Either for feed reliability, or because that was a cheaper way of making a chamber reamer, or maybe both.

 

[D. Manley]

OK. I am missing something. Does it give the "sized" looking front part as in the pics. The "Glocked" brass I have seen in 9MM only has a bit of a bulge in the rear above the web.

Looking closely, I see what you mean (I think). The image seems to show a fairly sharp break-line from the upper part toward the case mouth to where the "bulge" starts. If correct, no...I have'nt seen this. My .40 brass is bulged very similarly but the "curve" is pretty gentle and consistent on both ends with no sharply defined start or stop.

I don't have any spent rounds or I'd post a picture. Instead of going shooting, I've spent 2 full days making spreadsheets for the UniqueTek micrometer powder bar for Dillon measures...5 more powders to go and thankfully, done.

 

[1SOW]

About a 1/4" is pretty close to some 9mm seating depths.

As clean as the brass looks, doesn't that mean it sealed tightly to the chamber? It couldn't have been fired out of a CZ. Must have been a Glock.

 

[ArchAngelCD]

Nice pictures of the brass...

 

[Walkalong]

As clean as the brass looks,

I tumbled it.

 

[The Bushmaster]

And I'll reload it, Walkalong...As Fred said and I can't remember what firearm had the split chamber either, but I read about it several years ago.

I DO hope you picked it all up. It would be a shame to leave such fine brass to the weather...Or someone else.

 

[edSky]

I, too, have come across a number of 9mm cases with a "zip-line" going around it at about the same location. I've been trying to figure out what it was and my best guess at the time was maybe it as a 9mm AR-type rifle, or some other semi-auto that is non-standard. I attributed it to either some sort of feeding mechanism, but an odd chamber sounds good too.

(On an unrelated note, I've seen a lot of CCI and Blazer 9mm brass and the more I process cases the easier it is to spot them. They are the cleanest shiniest looking cases. The powder that was in them has to be some of the cleanest burning around.)

 

[Walkalong]

I DO hope you picked it all up.

You bet I did, and I'll reload it, thanks.

Oh, and I had never heard of a "split" or "two piece" chamber in a 9MM gun. Hmmm....

I just found it interesting since I had not seen any like this before.

 

[ArchAngelCD]

I've never seen brass look like that either. It does look fine after you resized it though.

 

[rbernie]

Oh, and I had never heard of a "split" or "two piece" chamber in a 9MM gun. Hmmm

BHPs use a two-piece barrel.