Danger of case head separation?

R

RileyMartin

New member
Attached is a pic of 30-06 South Korean brass (Stamped AK73). I shot this surplus ammo and have reloaded it once and about to reload it for a second time.

After decapping and cleaning it I went through the brass to check for cracks and such and put these aside due to the lines at the case head.

I don’t feel any groove at the line on the outside of the case.

I tried the trick with the paperclip with a 90 degree bend at the tip to feel for a groove on the inside and I’m not sure if I might feel a slight catching of the paper clip on the inside. It’s so slight I’m not sure.

How obvious should it be to be dangerous?

Thanks for any help.
 

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If its a cracked head then they are toast, and its not caution but pitch.

I can only see color changes in your picture.

If they don't look like the rest, certainly good reason for caution. Never shot any SK stuff so no idea what the rep is.

Side by side case with the ones you think are ok picture? Higher resolution camera more better for details.

What gun is it being shot in?

Two firings should not crack heads but not a given and SK brass and a gun combo, could happen.

As 303 Mil Surplus rifles are the worst, even those guys get 3 rounds.
 
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RileyMartin,

What your pic is showing is where the resizing stopped. If you had a situation of an incipient case head separation, you would have no trouble feeling it with you paper clip tool. I have just such a case that I bring to my class for demonstration purposes, and the students have no trouble feeling the groove in the web area on the inside of the case.

Don
 
I see nothing. You are going to get a visual change where you size the brass that will make it shiny but all of my brass looks like that. You are looking for a shiny ring all by itself. I had this same scare. I think it is just being over cautious. SOmeone correct me if I'm wrong.

https://www.google.com/search?client=firefox-b-1&biw=1920&bih=946&tbm=isch&sa=1&ei=wv-RWqrOCNSgjwPKmaroDA&q=30-06+case+head+separation&oq=30-06+case+head+separation&gs_l=psy-ab.3...323672.330965.0.331196.26.21.0.5.5.0.251.2226.7j12j1.20.0....0...1c.1.64.psy-ab..1.16.1435...0j0i67k1j0i24k1.0.6_w3IeWuRG4#imgrc=b0GI8r2mpNL_xM:
 
Can't upload photo.
Casehead separation is indicated by a distinct groove around or partially around the case maybe 3/8" from the rim. Tomorrow I will try again to post a picture. I don't see any indication of separation in your photo.
 
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Invest a few pieces of the brass that is worrying you in your peace of mind and education.
Hacksaw them in half lengthwise.File off the burrs.Study the inside of the case.
 
I see case head protrusion/unsupported case head. The shell holder plus radius prevents the case from being sized from the case head to a point .125" above the case heat + the radius. And then there is the chamber, the case head protrudes from the chamber.

F. Guffey
 
I picked out what I thought was the most significant of the 15 pieces of brass and cut in half with a dremel (should have used a hacksaw).

I saw no recognizable line, even under 3.5 magnification.

PIC attached.

I also included an uncut case to show where the line appears on the outside.
 

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That's not an over-expansion line on the outside. It is just where, as Mr. Guffey said, the inside radius of the sizing die comes to a stop when the mouth of the die contacts the deck of the shell holder. Nothing below that point gets resized and the brass is so thick that far down that is doesn't need to be unless you are shooting loads that are way too warm for the brass. If you look under magnification, you will see longitudinal fine die marks from that point up, but not below. If you had a second, different brand of sizing die with slightly different mouth radius to try, that line would move.

The kind of thing you are looking for is a line that is lighter in color than either the brass above or below it, is usually a broken line on one side of the case, and under magnification may appear porous because the brass has been stretched to the point it is starting to tear apart.

The bottom line is, that brass has a lot of life left in it.
 
M1a shooters learned not to use brass more than five times because the case heads would look like this.

C4x558F.jpg


120cPyI.jpg


I fired my 308 Win cases in my M1a's with a lubricant on the outside, and they came out looking like this, R stands for times reloaded:

7W5aJuk.jpg

6wVgbgx.jpg


I did not have any evidence of case head separations.

This guy obviously pushed the shoulder back too much and fired the cases dry, in a dry chamber:

ivZMmgt.jpg


Your sectioned cases look fine. As Unclenick said, what you have is mostly likely from the die, or the end of the chamber.
 
Thanks everyone for all the information.

I don’t personally know anyone who reloads so I’m learning all this by trial and error and everyone on here has been very helpful.

I’ve watched a lot of informative videos on YouTube. I know not to believe everything on there but there are some good instructional videos. I also bought the AGI DVD set ‘Reloading from A-Z’ when it was on sale.
 
The line on the outside of the case is where the sizer die stopped sizing. Nothing to worry about.
"...learning all this by trial and error..." Read your manual.
 
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