Brass Case Inserts

[Cockrbn]

Ran into this once before (2016) but haven't seen it again until today - using some range pickup brass. Does anyone know the purpose of the insert inside of brass cases from Freedom Munitions, specifically on 9mm parabellum. I have not found this on brass by other manufacturers. Does anyone reload them? If you do I am assuming yo reduce the charge because of the reduced case capacity. Thank you. :confused:

42313

[olstyn]

FM, IMT, and any others that have that ledge inside the brass go straight into my scrap jug with the spent primers. I have personally seen one of those cases split in a friend's chamber along that ledge. The sharp edge is a stress riser, so in addition to causing reduced case capacity, it also creates a "nice" spot for the cases to fail. Admittedly the failure I saw was with 9mm loaded to major PF in an Open gun, but even so, 9mm brass is basically free, so IMO there's no point in risking it, even if you're only loading minor.

[Jim Watson]

I thought my minor loads insulated me from trouble with "stepped" brass, but I finally managed to cut one in half. A reversed brush pulled out the front half but it was sure an interruption in the night's activities. A friendly penny ante game, they even let me restart the stage after I got the chamber cleared.

So now I am looking in the case for a ledge as well as for the presence of powder as I place a bullet on the press. I have discarded several.
I am just keeping my fingers crossed that I can get through the loaded ammo on hand without another separation.

[olstyn]

I am just keeping my fingers crossed that I can get through the loaded ammo on hand without another separation.

The headstamps I recall seeing with the ledge are FM, IMT, and AMMOLOAD. Might want to just check through your loaded ammo for those headstamps and at least cull them from the ammo you plan to take to matches and put them in a "practice only" bin. It's one thing to have a nasty stoppage like that when you're practicing, but I really wouldn't want to have a repeat of that match experience. Getting to restart a stage like that is pretty uncommon...

[Trooper224]

It's not an insert, it's a ledge manufactured in the cases interior. The only possible use I can see is to prevent bullet set back.

[Galbraith]

I've reloaded this brass before. No problems.

[Cockrbn]

Galbraith: Do you reduce your charge when reloading them?


I've reloaded this brass before. No problems.

Thank you to all who relied. I am going to try sectioning one of them. The FM headstamped cases I have appear to be an insert, not a ledge created during the drawing process.

[Cockrbn]

Galbraith: Do you reduce your charge when reloading them?


Thank you to all who relied. I am going to try sectioning one of them. The FM headstamped cases I have appear to be an insert, not a ledge created during the drawing process.

I did section one of the FM cases....it is definitely not an insert but looks to be drawn that way in manufacture. I still wonder "why" it is done. As a "bullet shelf" it seems to be pretty deep seating and a small charge space for a fast burning powder.

42363

[Velo Dog]

Quotes from https://forums.brianenos.com/topic/249758-stepped-brass/page/3/ ==>

"9mm brass made by forced extrusion rather than typical pressure drawing causes there to be that visible "ledge" about halfway down the case wall. It's just cheaper to make them using a forced extrusion method."

"The step is just an artifact from the manufacturing process."

It appears that the step or ledge is caused from the shape of the punch used in reverse impact extrusion ==> https://engineeringproductdesign.com/knowledge-base/metal-extrusion/

Reloading results ==> https://thereloadersnetwork.com/2018/09/11/is-it-safe-to-reload-maxxtech-ammoload-imt-fm-9mm-brass/


How cartridges are made by drawing brass ==> https://www.petersoncartridge.com/our-difference/drawing-brass/

[Cockrbn]

Velo Dog: Thank you for your knowledge. It appears I haven't kept up with current processes, part of being an old fart with 55 years of handloading experience - I must have thought I had seen or knew it all. I stand corrected and appreciate the mental adjustment and links. Time to do more reading. Thanks again.



Quotes from https://forums.brianenos.com/topic/249758-stepped-brass/page/3/ ==>

"9mm brass made by forced extrusion rather than typical pressure drawing causes there to be that visible "ledge" about halfway down the case wall. It's just cheaper to make them using a forced extrusion method."

"The step is just an artifact from the manufacturing process."

It appears that the step or ledge is caused from the shape of the punch used in reverse impact extrusion ==> https://engineeringproductdesign.com/knowledge-base/metal-extrusion/

Reloading results ==> https://thereloadersnetwork.com/2018/09/11/is-it-safe-to-reload-maxxtech-ammoload-imt-fm-9mm-brass/


How cartridges are made by drawing brass ==> https://www.petersoncartridge.com/our-difference/drawing-brass/

[Trigger]

I know the stepped cases jam up the swaging stage of my 1050 press. I hate them. I toss them when I find them.