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Tar Heel
04-01-2014, 01:37 PM
Users of PMC 38 Special ammunition or PMC 38 Special brass of recent manufacture should be aware that today I noticed some serious corrosion on scrounged PMC 38 Special brass.

After conducting a CCH course whereby four students used factory fresh PMC 38 Special ammunition, I went back to the range a week later to collect the fired brass and reload it. Included in my scrounging was 38 Special brass with WIN, Winchester, WW, IMI, R-P, and a spattering of military style head stamps as well as the targeted PMC head stamp.

All of the brass had been on the range during the rainstorms that week and some of the brass may have been there for longer than one week. Some of the brass looked the part and anyone who has scrounged brass knows what it looks like after a month or so lying on the range. Some like the PMC brass looked relatively good and shiny.

I cleaned all the brass in ground corn cob like always and most of it polished up just fine. Some had discoloration which normally means it is simply discolored. The PMC brass looked just fine. After a month in the shed, I went out to load the remaining brass which included the PMC brass.

The primers in the majority of the PMC brass would NOT eject down the ram and necessitated removing the shell holder to grip the primer flash with hemostats and rip it out. Upon inspection, it was apparent that the primers had severely corroded in their primer pockets and the majority of the primer was still in the primer pocket. Further inspection showed most of these cases also had white residue on the inside of the case where the propellant and firing residue has embedded itself into the brass.

ALL of the other cases with different head stamps deprimed normally and exhibited NO corrosion like the PMC cases do.

These cases are useless since one can’t manually remove primer parts with hemostats and there is no way to get the primer cup out of the primer pocket once the primer ‘cap’ gets removed from the primer.

I wanted to give you all a heads up about this PMC brass since the brass itself may be compromised. I can only conclude that PMC is using either a different propellant due to the lack of availability of their more common and preferred propellant and/or they may actually be using CORROSIVE priming compounds in the current ammunition. The residue seen reminds me of the corrosive priming compound residues we used to see decades ago.

Could this be a Cowboy Action Load using BP and the resultant corrosion?

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ReloaderFred
04-01-2014, 04:16 PM
It's not a corrosive priming mixture, and it's not something new with PMC ammunition. All the PMC ammunition manufactured in Korea leaves a white residue in the primer pocket, and once it gets wet, it cements the primer into the pocket and the bottom of the cup will separate from the wall of the cup, leaving the wall effectively glued to the inside of the primer pocket.

This was common with PMC ammunition all the way back into the early 1990's, but when the company was purchased and moved to Boulder City, NV, they were using CCI primers for the most part in their U.S. manufactured ammunition. When they went bankrupt, and the company was once again purchased by a Korean firm and moved back to Korea, they again started using the Korean primers, with the white residue.

It's neither lead styphnate nor Diazodinitrophenol (DDNP) priming compound, but I haven't researched it to find out what it actually is, though it's not corrosive priming as in mercuric priming compound. I just haven't been interested enough to really look into it, but it's nothing new and it's not going to damage your firearm.

Hope this helps.

Fred

tomme boy
04-01-2014, 05:04 PM
It is not just PMC ammo that is left in the rain for a week. All brass will start to show some form of green scum on the cases when left out in the elements.

Tar Heel
04-01-2014, 05:17 PM
Hope this helps.Fred

Thanks for the update. Whatever it is (chemically), I doubt it's good for the firearms.

Tar Heel
04-01-2014, 05:18 PM
It is not just PMC ammo that is left in the rain for a week. All brass will start to show some form of green scum on the cases when left out in the elements.
Yup. The green stuff comes out though and the primers decap. These don't decap and there is residue left in the cases after lengthy tumbling.

Thanks for the reply.....

fivegunner
04-01-2014, 07:04 PM
After reading the above post , I went and decaped 100 PMC .38 Brass that I found at the range. Yes some white powder was found in the primer pocket. 5 case`s did rip out the cap of the primer and there is no way to get the side of the primer out, I tryed for a hour , no way. these case`s looked like new . thanks for the heads up.[smilie=2:

GOPHER SLAYER
04-01-2014, 07:51 PM
I had the same problem with stuck primers in PMC 38 spl brass. Mine went into the scrap bucket.