Incipient case head separation?

[S Mac]

I bought a small lot of brass, 357, that the seller told me up front was an unknown # of firings.After sizing and loading a few of them, I noticed that some of them needed to be pushed a bit to chamber, and needed a bit more effort to extract after firing. When I size these cases again I tried to chamber the empty cases, still a bit large at the bottom of the case, about an eight of an inch from the bottom. I tried the paper clip trick to feel the inside and can feel nothing out of sorts. Measuring the outside of the case this ring is about .002 larger than above and below the ring. Think its the beginning of head separation?

 

[JWFilips]

I'm no expert but I would think if you used a sharped point on the paperclip to check the inside of the cases It would be noticeable there first. At least that is what I have found

 

[Ian]

Maybe someone got overzealous with annealing.

 

[S Mac]

I first though my sizer just wasn't sizing the bottom of the case, I faced a shellholder .003 or so the allow the case a bit more entry into the die, helped some but not completely. Maybe I need to take a bit more off the shellholder. The cases fit some of the chambers, but there are 2 that are a bit tighter.

 

[Rick]

Most likely I think it's been way over loaded and expanded the web of the case, Sizer die won't go down that far to size.

You posted while I was typing, I wouldn't mess with them myself. 357 brass isn't all that expensive or hard to get, were it me I would toss them.
.

 

[S Mac]

That sounds logical Rick. If that is the case then they would be safe to use, just an aggravation?

 

[Rick]

I wouldn't but that's just me I guess. If that case has been subjected to enough pressure to expand the web to my way of thinking it's a fine candidate for the trash can. Check the depth of the primer pocket, I would guess that if there was enough pressure to expand the web it also made the pocket shallower.

 

[Longone]

How did the primers feel when they were seated? Not always, but in some cases as Rick has mentioned, if the cased were used for some big loads you can usually feel the primer seat softly. Just curious, what dies are you using?

 

[S Mac]

RCBS carbide. Didn't notice anything odd while priming, and just the feel test on seating depth, haven't measured the primer pocket.

 

[Longone]

When in doubt............

 

[quicksylver]

Try the empties in another gun...

 

[Cherokee]

S Mac: Sounds like heavily loaded cases. Earlier this year I sold some older used Win SuperX and mixed brass, maybe to you, I don't recall. Anyway, if they came from me, the only heavy load they would have had was the factory load, after that, mid to lower range loads. However, I did have an old RCBS carbide die a few years ago that was acting up and the carbide ring finally came out of the die. Could be that die screwed up the cases and I did not know it. If you got them from me, I'll make it right.

 

[S Mac]

Try the empties in another gun...

Only 1 I've got.

 

[S Mac]

These didn't come from you Cherokee. And I'm not complaining, I was told they were well used. Just trying to figure out what the deal is.

 

[Cherokee]

S Mac: well, I would dump the cases that will not chamber and use the ones that will chamber for light or mid-range loads. I have had case head separation in old 38 special cases with WC loads, they can tie up your gun. The paper clip test should be good to ID potential separation...or just scrap and be done with them.

 

[9.3X62AL]

I think a couple things are acting in concert here. One of those influences could be higher pressure loadings, but I am more inclined to think a revolver or rifle with a bit more chamber diameter might have had "first go" with these cases. Some Marlin 94s can really go wide. Also be aware that RCBS T/C sizer dies leave a significant portion of the case above the rim untouched, and die setting specs say to leave a small gap between the die mouth and the shell holder additionally. Results can be that chambering of such brass can be difficult with more closely-toleranced charge holes.

I would not mess with a condition of this sort. I look at ANY brass distension with a jaundiced eye, and as a possible danger sign. The swollen brass can be restored to smaller diameter in a different die (e.g., an RCBS steel sizing die--they size a case a bit more deeply than do the T/Cs) but the net effect is to work the brass much like a sizing die does to 40 S&W brass fired in the older series Glock chambers that lacked the case head support now given to Gen 3 and Gen 4 Glock 40 & 10mm chambers. I am fairly certain that repeated swelling and swaging back of the swollen 40 S&W brass in these chambers was the proximate cause of the "Glock kB" events that used to occur from time to time in that caliber--Murphy's Law gets no plea bargains, and sure as hell that over-worked brass work-hardens--then weakens--and Murphy will see to it that the weakest portion of the much-used brass case will overlay the unsupported area of the chamber........and the results are at minimum memorable. While a revolver charge hole gives far better support than does an older Glock chamber/feedramp junction, you still are using these brass cups to contain from 36K to 42K PSI when you load the caliber to its 1935 capabilities. I don't know about other folks, but the ramifications of being casual about brass character and integrity are kinda sobering to me, and this goes double for magnum revolvers and high-powered rifles running at full potential. Sola mi dos centavos, compadres.

 

[Brad]

I agree Al. Messing with brass that has been potentially abused just isn't worth the effort. Always err on the side of caution.
My Marlin 45 Colt will easily make brass that won't fit another gun. Fire brass in a loose chamber then try to fit it in a tight one? Not gonna happen.

 

[358156 hp]

I've never had a 357 case separate on my, the only failure I've encountered was primarily cracks at the case mouth. I have had a few loose primer pockets over the eons too, but they seemed to be pretty rare in retrospect. If your cases are oversized in the web you can verify this by measuring the cases in that area and comparing the results to other cases from a different batch. I'd try measuring with a micrometer, rather than a caliper, but it all depends on what you have available.

If they're oversized, but otherwise in good condition you could try sizing them a little deeper by removing the innards from your sizing die, then screwing it in your single stage press upside down, then tapping a lubed case the die until it stops with a flat-faced soft hammer, or something like a nylon drift. Before you try this however, make certain you have a suitable rod handy to tap the cases back out of the die the other way. I've had to do this with old balloon head cases in my dark past. If you are doing this with a carbide sizing die, stop tapping the case in before it contacts the carbide sizing ring or you risk breaking the carbide ring.

The ring you speak of, is it just above the case rim, perhaps 3/16 inch or so? The brass could have been sized with a die that wasn't properly adjusted in the press. This can leave a bulge that sort of resembles a belt on one of the large old-fashioned rifle magnums. I primarily find these on 9mm cases that were sized in some of the more modern sizing dies that were redesigned when progressive reloading presses became so popular. These sizing dies have a much larger chamfer at the die mouth to help funnel the cases into the die. The downside is that they leave bulges near the base of the case which is what you might be seeing. I buy old (real old) Hornady Carbide Durachrome die sets, and equally elderly RCBS Carbides that have practically no chamfer at all at the die entry. Then I adjust these dies to cam over in my press to correct such issues.

Or, you could just toss the cases in the recycling bucket. Brass is still relatively cheap.

 

[Rick]

I don't know about other folks, but the ramifications of being casual about brass character and integrity are kinda sobering to me,

Absolutely! Exactly how I feel about any brass that I have any doubts, concerns or questions about. Compared to an eyeball or worse brass is just plain dirt cheap.
.

 

[Winelover]

RCBS carbide.

IMO, its just the nature of the beast.

Just went and took some measurements on the same lot of Winchester 357 Magnum brass that's been reloaded, different amounts of intervals. Once fired, 4 times, and 10 times fired. Always sized on RCBS carbide dies. The step becomes more apparent after each reloading. However, the measurements, always stayed the same. The web is .377 and the area, just above is .374 inches.



The same phenomenon, happens with 44 magnum and also 44 Special. It's not from overloaded brass, IMO. There is no way, I'm going to attempt to shoot Keith's or Skeeter's loads in a CA Bulldog.

No, I never have chambering issues, either.