Surprise! 9mm GROM brass..it's not brass!

FredB

FredB

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I went to the range today and cleaned up quite a bit of (other people's) pistol brass. When I got home I started to separate out the steel, Berdan primed stuff and ran a magnet over it. I was VERY surprised, to say the least, to see a bunch of "brass" hanging off the magnet! Turns out there were 31 rounds of this stuff in this batch. It has the appearance of brass both inside and out and is Boxer primed. All of it is head stamped GROM 9x19 PL.

I assumed it was brass plated steel but I am unfamiliar with such a product. I deprimed and resized several cases to see how much force was needed and I was again surprised when it sized with about the same effort as a brass case.

Anybody know anything about this stuff? I can't find anything useful online and I certainly don't need to mix it in with regular brass cases.
 
Thank you for the info and the site link, it was very interesting.
It appears that these cases are remanufactured in Poland from steel, boxer primed cases and then brass plated to target the commercial market. I suppose the purpose of the brass plating is simply for appearance.
Probably not a good candidate for further reloading.
 
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I've seen some zinc plated steel 9mm, Boxer primed. Looks for all the world like nickel plated. Pobjeda? headstamp. Oh, and they were also internally stepped cases as well.
 
DrScaryGuy said:
i suggest we form a partnership. You provide the photos, we'll collaborate on the jargon, and we'll make a million dollars on kickstarter to produce the long-fabled brass magnet.
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Here it is. The brass magnet. LoL. The steel .45 case is included for color contrast. Cases are not stepped internally. IMG_20210331_093237511_BURST000_COVER.jpg
 
MikeS. said:
I’ve read on this forum that they now have 10mm sp primer pockets in the world. 😠
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Yep. Did not realize it until somebody mentioned it. I went back a checked my stash, and sure enough I had some small primer 10mm. Same culprits - Blazer and Federal.
 
I didn't know about small primer 10mm. I think that's great! Now I have another source for .357 sig brass with the right primer size and these will have the correct neck length since they will form long enough to trim.
 
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Toprudder said:
Yep. Did not realize it until somebody mentioned it. I went back a checked my stash, and sure enough I had some small primer 10mm. Same culprits - Blazer and Federal.
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.....Federal NT head stamp?
 
Toprudder said:
Not NT. If they were NT, they would probably also be crimped.


I also like small primer 45. Having two primer sizes makes sorting them out a real pain, though.
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Interesting! I wonder if they went all small primer, all the time....

I remember small primer Federal, but seem to recall it being the Non Toxic stuff.
 
Desolo said:
Interesting! I wonder if they went all small primer, all the time....

I remember small primer Federal, but seem to recall it being the Non Toxic stuff.
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In the 45acp, Federal makes large primer, small primer, and NT (non-toxic) which were also small primer, but I am pretty sure the NT were crimped in place. Win also makes NT, which are small and crimped. I've seen the NT in 40 and 9mm as well, and crimped.

I don't know if Federal has transitioned to all small primer in 45acp. Blazer used to make large primer 45, but they only make small primer now, and I believe that happened 6 or more years ago. I've also seen Speer in small primer, and RWS as well.

But we have gotten way off topic.
 
I found some 9mm that shows a where the bullet seats. Looks like how a revo cylinder is cut. Wider at the top, narrower further down. Is that "internally stepped"? What is that for? Seems it would increase pressure from the reduced case volume.
 
Thumbsout said:
I found some 9mm that shows a where the bullet seats. Looks like how a revo cylinder is cut. Wider at the top, narrower further down. Is that "internally stepped"? What is that for? Seems it would increase pressure from the reduced case volume.
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17592B74-772B-4BB2-9C91-5337D5EB9258.jpeg

The step may be more pronounced, and be closer the the case mouth, depending on the headstamp. Most conventional 9mm brass have a constant wall thickness for the first 0.2” below the case mouth, and then taper in thickness (thicker) as it gets closer to the web.
 
Geco Brass is stepped like that , isn't it? Mr Rudder?
 
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Wahoo95 said:
[emoji1787][emoji1787][emoji1787]....I actually like small primer 45scp brass.

Sent from my SM-N960U using Tapatalk
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I don't disagree, but it's kind of like saying "I have an idea, let's make all Coke product bottle caps Left Hand Thread".

Mike Dillion, along with all other progressive reloader manufacturers should have pushed the inventors of SPP 45 out of his helicopter.
 
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JohnFreeman said:
Geco Brass is stepped like that , isn't it? Mr Rudder?
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I don't remember if Geco is stepped ( I don't seem to remember that it is ) but there are others, like Ammoload, FM, IMT? some of the early Maxxtech, etc. Seems like there are about a half dozen headstamps that have the internal step.

The internal step may or may not affect the internal volume. The one I posted a photo of I don't think will affect the volume, but the Maxxtech stepped cases I'm sure would. Some people have speculated that the step is to prevent bullet setback, but that is not the case for some of the headstamps (like the one in the photo) as the step may be way too deep for that.

One known issue with the stepped cases is that the step concentrates the stresses at the point. For blow-back actions, where the case is starting to extract before the chamber pressure has dropped, can (and has, in many instances) caused case separation.
 
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Toprudder said:
I also like small primer 45. Having two primer sizes makes sorting them out a real pain, though.
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When I first started reloading and hadn't learned enough to tell the difference just by looking at the brass, I made a small gauge for the two sizes. It helped a lot until I can now tell just by looking at the casing...

SAM_1069a.jpg
 
Harold2689 said:
When I first started reloading and hadn't learned enough to tell the difference just by looking at the brass, I made a small gauge for the two sizes. It helped a lot until I can now tell just by looking at the casing...

View attachment 322383
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I made a 50 round tray with 5mm screws in the bottom. I can dump a pile of cases on it and the cases mostly go in head first (heavy end) and the small primer brass will stand proud of the large primer cases. A plus is that it works for the 10mm cases as well.
B8BD631E-3BD8-4B69-B1C9-969597060C80.jpeg
 
Toprudder said:
I made a 50 round tray with 5mm screws in the bottom. I can dump a pile of cases on it and the cases mostly go in head first (heavy end) and the small primer brass will stand proud of the large primer cases. A plus is that it works for the 10mm cases as well.
View attachment 322386
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Now, that, that is something I bet people would buy.
 
FredB said:
Thank you for the info and the site link, it was very interesting.
It appears that these cases are remanufactured in Poland from steel, boxer primed cases and then brass plated to target the commercial market. I suppose the purpose of the brass plating is simply for appearance.
Probably not a good candidate for further reloading.
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S&B had some brass plated steel 9mm for a while, turned pink if wet tumbled. I loaded it, never had an issue. Seems like I've come across others. I'll load almost any pistol case, I loath sorting.
 
That's interesting. I deprimed and sized a few of the Grom cases and did not see any differences in the effort required. I reload on a rockchucker (single stage press) and I wonder if this kind if brass plated case would cause problems for someone using a progressive press? I suspect that even if they reload ok, the cases will start to fail after a few reloading cycles as the steel work hardens.
 
I load on a LnL AP. Anything different feeling gets inspected it's usually a problem. Those S&B's did have a slightly higher reject rate at the gauge than domestic brass.

I'm not encouraging loading steel cases, just relaying experience. If I ever have major problems from them I'll add a big magnet to processing. Can't speak to longevity, too lazy to sort is definitely too lazy to track that, specially when it gets all intermingled with other's brass at the range.
 
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