Ever Seen An Internally Belted 9mm Luger Case?

[Liberty1776]

I have thousands of 9mm brass cases, scrounged from the local range.

I found one case with a belt on the inside. See the pictures.

The head does not indicate +P.

There is not another case stuck inside. The flash hole is clear.

I didn't reload it for fear of overpressuring.

Could it be an attempt to strengthen the base of the 9mm to avoid "the Glock Bulge" due to the unsupported area at the barrel loading ramp?

Any ideas?

[high standard 40]

I've seen those. My thought was a subsonic loading. This case would have reduced internal capacity and would have better load density with sub loads.

[nhyrum]

Yes. There are a few other headstamps as well. From what I understand is it helps get chamber pressure up for really light loads, due to the reduced capacity. I believe this to be the primary reason, because it's mostly find in cheaper and weaker ammo.

Yes, the thicker brass could help with the Glock bulge, but I don't think that's the reason, if it was, I think you'd see more of it coming from brass manufacturers and being made available to reloaders, not something only ammo manufacturing facilities get, since they don't really care what happens after the first firing.

They could be reloadable, they would just have to have their own data, and have a batch of identical cases

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[Liberty1776]

Makes sense.

So, you would recommend not to reload with a normal powder charge?

I have so much 9mm, I'll just put this sample in the archives.

Quite the oddball case....

[nhyrum]

So, you would recommend not to reload with a normal powder charge?

Correct. It would only make sense to keep if you were really after getting the smallest powder charge in the case and have functioning ammo, and that's the only brass you have/use. I'm not a fan of trying to sort through brass for something so small and easily missed.

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[Liberty1776]

Correct. It would only make sense to keep if you were really after getting the smallest powder charge in the case and have functioning ammo

Subsonic would be for suppressed "tactical" 9's that need to cycle the action?

My Walther PPQ Tactical with threaded barrel comes with two recoil springs -- a separate recoil spring if a suppressor is screwed on.

I've seen some videos where a suppressed 9mm gun was less than reliable with certain ammo.

I can see where it would be tricky to have "quiet" subsonic ammo, and a suppressor, and a different recoil spring, and still have have enough "oomph" to cycle the action reliably.

[Driver man]

This is quite a common case type found here. The common load for these is 115 grain and they don't fit your standard decapping dies due to the internal lip. I believe that these cases are made to eliminate bullet set back.
I reload these by decapping with a home made decapping tool but as case capacity is considerably reduced due to the lip so have dropped the powder charge by half a grain or so. I have found these cases to give me the most accurate loads in my Glock and CZ

[popper]

IMHO several reasons. 1) 9mm is normally a tapered case, these are not. Most modern pistols work well with non-tapered cases.
2) prevent setback
3) Thicker wall in the powder area.
4) 9mm was for machine gun use, taper needed.
Amscor seems to be the HS I see most. Not bad brass but I toss in the scrap bucket as I load cast and my bullets don't fit.

[Bmi48219]

I’ve seen Mag Tech 9mm brass with an inner shoulder but it was taller than the OP’s pic.
Another good reason to sort your brass.

[RydForLyf]

Yep, right into the scrap bucket they go.

[armoredman]

Any time I find those in my brass I scrap them.

[fatelk]

I pick them out too, but I have a very specific use for them. I trim them down to make 9mm Makarov brass.

Regular 9mm brass gets thick towards the base of the case. These are thin down to the step, where they're thick all at once. 9mm Makarov brass, being shorter, seats the bullet farther down, and some regular 9x19 brass tends to bulge at that point. This stuff, being thin further down, makes great 9x18 brass. They've also easier to sort that way; if I see the step, it's 9mm Mak brass, or soon will be.

[ioon44]

Yep me too, right into the scrap bucket they go.

[dverna]

Interesting....I have never seen a case like that. But my 9mm cases are from US companies. Never seen an IMT headstamp. Makes a bit cautious now as I never inspect 9mm cases. If they load without the neck splitting they are good enough for me. I load about .3 gr below maximum for cast plinking ammunition so it may not be much of a concern.

[alamogunr]

I have found one case like that. I can't read the head stamp and I'm not sure now where I found it. It could have been in some purchased OF cases. This case has the primer pushed out about 1/32". It apparently fired OK but not sure how it ejected. Would have thought the spent primer would have been reseated by pressure against bolt.

[kevin c]

Action pistoleers use a lot of 9mm brass, and finding internally stepped cases is common. Out my way (California) I found IMT (International Munitions and Technology), Ammoload and FM (Freedom Munitions), all owned by the same US group that sells its own branded loaded ammo and also components to other manufacturers. Then there's MaxxTech, which is Bosnian.

I've read that the IMT and Ammoload markings are older ones, and over time I've seen less of those and more of both stepped and regular FM cases, and most recently mostly regular FM. MaxxTech cases are common, and again recently, IIRC, it's mostly regular cases now.

There are warnings all over the shooting forums about case separations with the stepped brands, but I've only found one such case (I didn't load or shoot it), and on a range where almost everybody reloads and many loads are fairly hot, one example isn't enough for me to generalize from. So, being curious and having the time, I ran a test: I got 500 once fired FM cases from a non reloading shooting buddy, marked them and then reloaded, shot and recovered the cases for further reloading, repeatedly. The load was a 147 commercially cast coated bullet loaded to SAAMI spec and stepping out at about 900 fps through my OEM Glock barrels. There was no interference of the step with the bullet base, though I should note that the slugs were bevel based. By the time I gave up, I'd shot the remaining cases (300 odd) something like fifteen times. I had zero case separations, only mouth splits at a rate that seemed reasonable for the number of loadings. YMMV of course, but, while I was shooting random HS brass, I stopped worrying about it.

[mdi]

Yep, been showing up for a while now with many "factual" reasons for the design. Every forum this has been mentioned, the consensis is "trash them". They would probably be OK with a dedicated load work up, but 99% of the replies by 9mm reloaders is "round file
em". Google "stepped 9mm cases" for more "info" (?)...

[Valley-Shooter]

I find these case every once in awhile. My RL-1050 binds up at the primer pocket swaging station because it also expands the case with hold down rod.
They go right in the trash.

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[lightman]

I'm another that puts them in the recycle bucket. 9MM's are so plentiful that it doesn't bother me to scrap them.

[jmorris]

Stepped case. It’s to prevent set back. There are people that reload them, at least until a case separates.

They reduce the internal volume of the case enough that my powder check dies catch them.