Brass issue, bulged cases and incipient case head separation

[psale63]

Hey guys, I'm new to reloading and I need some help identifying a brass issue I've encountered.

I recently bought a complete used relaoding kit along with brass and dies. The brass that came with the kit is 243 Win, 270 Win, 30-06 Sprg and 7mm Rem Mag. and I have no idea how many loadings this brass has seen. Much of the brass was heavily tarnished from a few years of storage so I cleaned up the brass in a tumbler to make inspection easier. What I found in about 40% (~120pcs) of the 243 Win, 270 Win and 30-06 Sprg cases was bulges near the bottom of case.

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The worst of these bulges measure 6 thou larger than the case head. So I hit up the web to try and find out what these bulges meant. I read everything from "this is normal", to "base rings", "web separation" and "incipient case head seperation". Thinking I had a case of incipient head seperation I used the paperclip method to see if I could feel a divot inside the brass case. I didn't notice anything and I didn't like the feel of the paperclip so I then used a dental pick to see if I could locate a divot, still nothing. My next step was to section a case to see if there was anything obvious inside that I could see. On first inspection I did not notice anything UNTIL I shined a flashlight down the case mouth and I could see the very slightest divot on the inside of the case.

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This confirmed my suspicion of incipient case head separation but with how bad the bulges were on the outside of the case I was expecting a much more obvious divot on the inside. So my questions are:
Are these two conditions usually seen together or are they two separate issues?
I understand what causes case head separations but I've never seen bulging like this, Is this caused by over pressure? Or oversize chamber?
And finally is this brass safe to load?

I have all of the bulged brass culled out but I'd hate to toss it if it's serviceable, I would hate even more to have a case come apart during firing though!

 

[H4831]

Short answer is quit worrying so much about it and trying to find something wrong.
The cases in the pictures as well as the .006" bulge is not far from normal for a good many rifles.
Was this brass shot in the rifles you have?
If they were, you should give your sizing die a bit of clearance to the shell holder, so it won't push the shoulder back. Try one partially sized, then try it in your rifle chamber. If the bolt will easily close on the case, consider it sized.
If the brass has not been shot in the rifle you have, it will require full length resizing.
However, before you resize the cases you should by all means, anneal them.
If you are not familiar with annealing, here are the basics of important information.
Never, ever, heat the bases of the cases.
The old standby, kitchen table method of annealing is as follows.

NOTICE- I am going to state an old method of doing it. There are many variations, but I am not going to get involved in any peeing match on annealing.

Take the primers out of the cases. Get a flat bottomed pan, quite large and put 3/4 of an inch of water in the bottom. Stand the cases upright in the pan, in the water. Leave some clearance between cases.
You have to heat the tops of the cases. For this the one litre butane tank torch works fine.
Turn the lights in the room off, or very dim. Centre the heat from your torch on the area around the shoulder of the case. When it shows the dimmest of red, upset it in the water.
The heat treatment will make it much easier to size and greatly lengthen the useful life of the brass.

 

[9.3mauser]

Like H4831 says, those cases are not abnormal. The " bulge" is caused by chamber tolerances. Incipient case head separation looks like this: notice the bright ring on the case on the right.

 

[bigedp51]

AMpsale63

What you are seeing is very simple, the base diameter of your pictured cases are smaller than the base diameter of your chamber. American made cases tend to run on the small side of manufacturing limits and what you see is normal. If you look below the base diameter of the 30-06 case can be from .4698 to .4618 and be within manufacturing tolerances.

Below are two .303 British cases fired in the same Enfield rifle, the only difference is the Greek HXP case is smaller in base diameter than the Privi case, and both of these cases did not stretch and thin in the base web area when fired.

There is a difference between the case expanding to contact the chamber walls and stretching and thinning to meet the bolt face. The factory loaded Winchester .303 British case below stretched and thinned .009 on the first firing.
This Winchester case was designed to shoot in shorter headspace commercial rifles and NOT in a military rifle with longer headspace. And this is why military cases last longer when reloaded because they are built Ford truck tough.

I have brass OCD and check my cases with a RCBS case mastering gauge, I do this because I have so many milsurp rifles with chambers "LARGER" than the drawing above showing "civilian" SAAMI standards. As an example a AR15 chamber is .002 larger in diameter and has longer headspace settings than a commercial .223 chamber.

Bottom line, welcome to the world of skinny brass cases and fat chambers, and this is normal in our plus and minus manufacturing world.

Below is an example of what you "thought" you had and what you want to look for before it happens, these .308 cases were reloaded and fired over and over until the cases failed and no damage was done to the rifle or shooter. This is why you should "ALWAYS" wear shooting glasses when firing reloads to protect your eyes "IF" any gas leakage blows to the rear and this depends on your rifles gas venting design.

The case head separations above are caused by the quality of the brass used in manufacture and "HOW" you set up your reloading dies. On a bolt action you only want .001 to .002 shoulder bump and .003 to .004 on a semiauto, meaning if you set up your dies per the instructions you can over resize the case.

Below is an animation of a case being fired, the distance between the rear of the case and the bolt face is called head clearance. And when the head clearance is excessive the case will stretch and thin in the base web area. And again this depends on how the brass is made, the rifles headspace and how much shoulder bump the case gets during resizing.

Below is an example of resizing, on the far left you see your "NORMAL" pressure ring, shoulder bump and shoulder setback describe the same thing and pay attention to the blue, red and green dotted lines. (how you set up your dies)

Your doing good, keep inspecting your cases before and after sizing and you will do just fine, as a side note I have been reloading for over 47 years and have had a complete case head separation.

NOTE, read the front part of your reloading manuals, you will find a wealth of information and it is far to often skipped over and never read.

"All the information in the world is written in books and all you have to do is read"

 

[blargon]

With unknown number of firings, i would probably start with new brass.

 

[Lead Loader]

Just size and shoot. No need to worry unless there is an apparent failure or primers fail to seat in or are loose.

 

[bc308]

This thread should be mandatory reading for all new reloaders. It's the walking step before trying to run.

 

[psale63]

Thanks H4831, I'll try not to be so paranoid in the future!
I haven't shot any of this brass in my rifles yet but my plan was to FL resize first, then size until the cartridge just fits the chamber for subsequent reloads. I have been doing some reading on annealing, and I do plan on trying it with some of this brass.

 

[psale63]

Wow, Bigedp51! That is a wealth of information, thanks for the thorough, easy to understand response!

 

[H4831]

Thanks H4831, I'll try not to be so paranoid in the future!
I haven't shot any of this brass in my rifles yet but my plan was to FL resize first, then size until the cartridge just fits the chamber for subsequent reloads. I have been doing some reading on annealing, and I do plan on trying it with some of this brass.

OK, but. A tremendous number of rifles out there, especially the newer ones, have actions so tight and such minimal head space, that brass has to be full length resized every time.
What I am saying is don't just partially size the brass, unless that rifle shows a visible ridge ahead of the base. If the shot brass comes out looking like it did when it went in the chamber, full length resize every time.
Couple of years ago I got a custom made 243. I full length resized some old brass I had around, but discovered the bolt wouldn't close on them! I redid the full length sizing, putting all the pressure I could on the die, but still no luck, they wouldn't go in the chamber and have the bolt close on them. I thought I had an undersized chamber, but found that factory loaded cartridges worked fine.
The answer was on my old brass the shoulder would be pushed back, but the hard brass just sprung ahead again, when it came out of the die. When I annealed the brass it worked flawlessly after full length sizing.
A year ago I bought a new Marlin bolt action 243 and it was exactly the same! Old brass would not go back in the chamber until I annealed it.
Now I have found the same thing with a new Tikka in 7-08 I just got. I had a heap of brass from another rifle, I full length sized it, but the bolt wouldn't close on it.
I annealed it, resized it and it works fine.
That is why I recommended that you anneal your old brass and also why I say forget about a partial resize, unless there is a sound reason to do it that way.

 

[psale63]

OK, but. A tremendous number of rifles out there, especially the newer ones, have actions so tight and such minimal head space, that brass has to be full length resized every time.
What I am saying is don't just partially size the brass, unless that rifle shows a visible ridge ahead of the base. If the shot brass comes out looking like it did when it went in the chamber, full length resize every time.
Couple of years ago I got a custom made 243. I full length resized some old brass I had around, but discovered the bolt wouldn't close on them! I redid the full length sizing, putting all the pressure I could on the die, but still no luck, they wouldn't go in the chamber and have the bolt close on them. I thought I had an undersized chamber, but found that factory loaded cartridges worked fine.
The answer was on my old brass the shoulder would be pushed back, but the hard brass just sprung ahead again, when it came out of the die. When I annealed the brass it worked flawlessly after full length sizing.
A year ago I bought a new Marlin bolt action 243 and it was exactly the same! Old brass would not go back in the chamber until I annealed it.
Now I have found the same thing with a new Tikka in 7-08 I just got. I had a heap of brass from another rifle, I full length sized it, but the bolt wouldn't close on it.
I annealed it, resized it and it works fine.
That is why I recommended that you anneal your old brass and also why I say forget about a partial resize, unless there is a sound reason to do it that way.

I'll be sure to anneal and full length resize this brass, thanks for your help!
I'm sure I'll end up over annealing a few pieces, good thing I have some extra kicking around now!