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Discussion Starter #1 (Edited)
I am recommending that you use extreme caution if you are reloading any 40 cal. PMC cases. The cases that I had were of two part case construction and the base had been expanded into the side wall portion. I recently had two cases come apart when fired in my S&W Mod. 4006 pistol. I was firing a batch of 100 mixed brand cases that had been once fired and reloaded with a conservative load of 4.7 gr of Red Dot behind a 180 gr LSWC.

The two PMC cases blew apart upon firing, sending a tremendous blast down and out of the trigger area and along side the clip. Both case walls remained in the chamber and both case bases were found directly below the gun, at my feet.

I have since sorted out more than 3000 rounds of cases and thrown out every one of the PMC's. I have dissected several once fired PMC's in 40 cal and 45 auto to take a closer look. The seam joint is very obvious in the 40's, but the 45 ACP's were found to be made by standard one-piece construction.

I would recommend that you check any 40 cal PMC's in your supply and take the appropriate steps. In 45 years or more of reloading, I have never seen this type of case or experienced such a separation and scare.

Cut and past this link to view a photo report on the erupted cases: http://www.coreyhughes.com/misc-info/PMC.jpg




Reload safe and live long………

Corey
 

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Welcome to the forum. Rules are to join in and have fun and play nicely with the rest of us kids.

Thanks for the heads up. I have moved your post to the handloading forum where the topic is most apropos.
 

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Welcome to the forum. Rules are to join in and have fun and play nicely with the rest of us kids.

Thanks for the heads up. I have moved your post to the handloading forum where the topic is most apropos.
Nick: Thanks, I was having trouble posting this mornign anyways. I just added a photo link of the erupted casings and the ones I disected for a closer inspection.

Corey
 

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It's pretty clear that metal fold you're calling a crimp at the case head is the problem area. Not much brass for the rounds to hold on through. The Red Dot load appears to be a maximum load, but not over SAAMI. It is perfectly possible that PMC loads these with a powder that doesn't reach maximum pressure, so they don't notice the problem.

For example: QuickLOAD shows your Red Dot load getting almost 34,700 psi, while it shows 5.3 grains of Hodgdon Universal getting the same velocity from a 4" barrel with a peak pressure of only 27,500 psi. Just over 20% lower pressure.

What is curious is that fold. It looks like the forming dies just didn't hit the brass hard enough to forge a normal head from the cup. Inadequate work-hardening at the head also means the brass will have less tensile strength than a properly formed head; too weak to hold pressure well.
 

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I reloaded a bunch of PMC in 45ACP and never had a problem but of course 45 is running at some pretty low pressures. I definitely won't reload any PMC 40s. Thanks for the report.
 

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I wonder if that's normal or a defect? If anyone else has some PMC .40 they could slice up and look at, the feedback might prove interesting?
 

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I've been watching this thread with interest. I couldn't imagine that PMC used a brass cartridge case of two piece construction, but I suppose anything is possible. Following Unclenick's advice, just a little while ago I sectioned a few .40 S&W cases with the PMC headstamp. All that I cut up were made from a single draw of brass, which is the usual construction.

The reason I've been watching this thread is because I've always had the impression that PMC brass was of very good quality. My experiences with it have shown it to be stronger than some other makes without being overly thick. At present, some of the 7.62mm NATO ammunition that is used by the US military is made by PMC. PMC is a large company, so it may be possible that they get brass from different sources (either from their own multiple plants or outside vendors). The brass I have used myself in many different calibers has always been quite serviceable.

I no longer load for .40 S&W, but still have some brass around. I used to shoot it in a Ruger .40 caliber carbine. After one return trip to the Sturm, Ruger factory in Arizona, the carbine was set up to shoot anything, including cast lead bullets. My tendency is to load down, not up, but I am aware of the problem of insufficient case head/web support in the Glock pistols. I never had any problems of that sort with the Ruger carbine.

Loading cast bullets can introduce other problems into handloaded ammo beyond that found when jacketed bullets are used. Selection of brass can be important so as to be compatible with the bullet used. In this connection, I never had any problems with .40 S&W brass made by PMC.

The cautionary information given out by the OPer should be observed, however.
 

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I doubt it's two-piece. I think they just screwed up the draw from the cup. They may have tried to do something with one die rather than two steps and wound up foreshortening the the original cup with that lap fold. Other lots may be fine. It would be worth checking before reloading some.
 
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