case head separation

[possum6]

What causes case head separation   Is it alway's high pressure   Just had one happen, came in and wiped   No seriously first time I've had it happen. Sure would appreciate some input.

[cwlongshot]

It can be caused by a couple things, but too high a pressure alone is not one of them...

When most cases are made, they are drawn from a brass discs, As the case forms it thins rapidly a short distance up from the web. If you have too much head space in the chamber the brass will stretch to accommodate the chamber. It stretches at this thing of the case, the result is case head separation. Its often an incremental process, but a very high pressure round in such a chamber can do it.

What was the firearm and what was the ammo?

CW

[possum6]

243 Handi, winchester brass, winchester LR primer, IMR 4320-37.7g, 70gr. Berger, seated close to the land's if not touching. Just looked at the brass of the 3-shot group, should have looked at the second round when ejected [learnt my lesson there] it was starting to separate. Brass is on third loading with F/L sizing. I'm hoping it's the brass. Would the gun have anything to do with it? 

[stimpylu32]

May be the rifle but most likely the brass or a combo of the two . Handi's do flex some allowing the brass to grow faster than a bolt gun would .

If I had to guess as to what to check first , it would be your die setting , sounds like your bumping the shoulder back just a touch too far and causing a headspace issue .

stimpy

[cwlongshot]

OK, That was my next question. Improperly adjusted loading dies can also mimic a headspace problem.

I would first suggest you look at your dies, I'm going to guess that your pushing the shoulder of the brass back with each subsequent loading, resulting in a very thin ring around the brass. Look at your cases, its probable that you will be able to see the lighter brass showing the incepent separation.

CW

You  just a bit quicker Stimpy.. 

[stimpylu32]

And before you load the rest of them anymore , take a paper clip , straiten it , put a small bend on the end of it and run it into the case , if its starting to come apart you'll be able to feel the crack inside before you see it on the outside .

If you feel the crack --- Toss them in the scrap bucket ! 

stimpy

[possum6]

No doubt I think I'll toss them anyway. What does head separation do to the gun?

[possum6]

I posted here while back about the gun not closing up good. I thought it was my cases. Adjusted my dies slowly so there would not be any daylight when round was in the gun. Got to looking and when I pull down on barrel with action closed I see the space I was seeing with the cartridge in the gun. If you understand what I mean.

[stimpylu32]

Not alot in most cases , does cause a headache when the top 1/2 of the case is stuck in the chamber and your only way to get it out is at home , not with you . 

stimpy

Sounds like you have a slight lock-up problem , the pivit point may be a bit loose on the pin , check the Handi FAQ's in the H&R Centerfire forums for more info as to a fix .

[possum6]

The top of the case came out no problem. What should I do with the other cartridges that I made up? Pull them or take the chance? stupid ?? I guess.

[stimpylu32]

You can do either , if you do shoot them , make sure you have a cleaning rod with an over-sized brush along to push the rest of the case out if they do come apart . 

Myself , I'd pull them just to avoid the hassle and start with new brass after you have the lock up issue delt with .

stimpy

[cwlongshot]

OK, Stimpy provided some excellent information.

I too would pull those bullets, harvest the powder and toss the brass.

Do you know how to set up your dies, using new brass that was fired from your rifles chamber?

Your one phrase "Until there would not be any daylight when the bullet was in the gun" has me concerned. Ultimately this is what you need, its just there is a better more exacting to do it.

CW

[Dave in WV]

With a .243 you need to trim more often than most other cartridges. A RCBS X die stops cartridge "growth" but you have to trim the cases once after the first time fired. Smoke the neck area of a round of your fired brass. Adjust the resizing die out so it doesn't resize the neck all the way down to the shoulder and then run a lubed case with the smoked neck in the die. Keep adjusting the die down until you wipe the soot off just above the shoulder. If the action doesn't want to close normally, remove the decapping stem from a .45 ACP carbide resing die and run your brass through it and see it it helps. The .45 ACP die will only squeeze the web area of your brass.

[possum6]

Appreciate all the help guy's. Finnally got hold of my [ reloading mentor ] he was out of town. Everything yaw said though was right on the money. When I told Charlie what had happened he cracked up.  Am I the only one that butt-cheek's draw up when something odd happen's

[Brithunter]

I have one rifle that kepp aplitting the cases about 1/3 of the way up the case. This was new factory although old stock ammo. At first i thought it was brittle brass but then noticed that the cases wer enot round but lobed  this barrel had be re-lined some time bach when God only knows. The rifle is pre 1924 as far as I can tell. So after a wait and a search a new barrel was found an fitted and Hey presto no more cracked brass.

There are several things that can cause a case seperation so you need to carefully examine the gun and make sure that it's not the culprit.

[Steve P]

Check out your previous thread:  http://www.gboreloaded.com/forums/index.php/topic,191075.0.html

Case head separation was mentioned.  You set your sizing die to your gun, not to the die directions.  The die directions are a reference or starting point.  Your chamber in your gun may not be same same as your dies.  Chamber reamers and die reamers wear with use.  They will be within spec, but can be at opposite ends of the tolerance.  Adjust your die so your fired brass fits into the chamber with a solid and firm closure.  If you can easily close your action on a sized once fired brass, you may be "over sizing" the brass for your chamber. 

If it were me, I would toss any brass with multiple firings after full length sizing.  May not separate today, but might tomorrow when the big whitetail is in your crosshairs. 

Steve

[Blackhawker]

Possum,
Forgive me for not reading the entire thread as what I'm about to say may have already been mentioned.  If not, then hey, maybe I've got some help for you.

I had some problems with my 30-30 on my TC rifle.  I was checking bullet seating depths with my T/C pistol barrel.  Little did I know, the throat of the rifle barrels is a little shallower than the pistols for some reason.  Every fourth or fifth time I fired my rifle, I had cases that split around the web or showed that characteristic white line.  It was driving me crazy because I never had seen this before in the course of the past 20 years and couldn't imagine what the heck was causing it.  I had found a good deal on a new barrel, thinking it was my chamber or something and I got the same results with a new barrel too.  What I later discovered was that my rounds were seating on the bullet and the lands, NOT the rim as a 30-30 should seat.  This caused an ever so slight lengthening of where the case should have seated and although the chamber closed, the round was unknowingly sticking out of the chamber slightly.  That was enough for the web to expand too far into the chamber and cause a case head separation...or the white lines that indicate brass thinning. 
So, lesson learned for me.  The message I send along to you is to check your bullet seating.  Be sure you're not seating on the lands as opposed to the headspace of the cartridge.

[Lone Star]

What I later discovered was that my rounds were seating on the bullet and the lands, NOT the rim as a 30-30 should seat.

BH, most all bottlenecked cases should headspace on the shoulder, not on the rim.  "Seating on the bullet" as you describe is not a problem for case head separations or case thinning - not setting your die to headspace on the shoulder is the problem.  You will have the same case problems even if you seat the bullets 1/4" deeper but don't change the setting on your FL sizing die.  In fact, "seating on the bullet" can actually prevent excess headspace and case separations, it is a commonly-used method to fireform new (short) brass in an oversized (long) chamber.  

The other problem with .30-30 case life has to do with the springy action of the M94, but that usually happens only when using excessive chamber pressures.




.

[possum6]

I hope it never happen's again, glad it did though. It got me really looking at my gun. Stopped trying to work-up load's for this gun long time ago because of the so called [ headspace problem ] " long story ". Worked up some load's today with some new brass. First 3-shot group was 1 3/8". Took them once-fired case's and neck-sized only. The next 3-shot group was touching if not some over-lapping . If I hadn't had the case separation I never would have neck-sized for this particular Handi again. I did find out this gun does stretch brass or let it flow more than normal.

[Blackhawker]

What I later discovered was that my rounds were seating on the bullet and the lands, NOT the rim as a 30-30 should seat.

BH, most all bottlenecked cases should headspace on the shoulder, not on the rim.  "Seating on the bullet" as you describe is not a problem for case head separations or case thinning - not setting your die to headspace on the shoulder is the problem.  You will have the same case problems even if you seat the bullets 1/4" deeper but don't change the setting on your FL sizing die.  In fact, "seating on the bullet" can actually prevent excess headspace and case separations, it is a commonly-used method to fireform new (short) brass in an oversized (long) chamber.  

The other problem with .30-30 case life has to do with the springy action of the M94, but that usually happens only when using excessive chamber pressures.
.

Lonestar
Ironically, when I seated the bullets back a bit, I never had the problem again. In my case it WAS the seating of the bullet being too far into the lands. 
Also, it is my understanding that when dealing with a rimmed cartidge such as the 30-30, the cartridge is supposed to seat on the rim.   I typically full length size my brass for my 30-30 so it is almost impossible to have them headspace on the shoulder.  If I were to only neck size only, then I could better seat on the shoulder.  With rimless cartiges such as .223's etc, these type of cartridges seat/headspace  on the shoulder. 

[MZ5]

Just to be clear:  You can still headspace a rimmed cartridge on the shoulder.  Sizing die adjustment accomplishes this.  Even if sizing to headspace on the rim, one should still adjust the sizer for minimum 'gap' (headspace) between the cartridge shoulder and chamber shoulder.  Sizing any shorter merely work-fatigues the brass way too soon.

[Blackhawker]

Just to be clear:  You can still headspace a rimmed cartridge on the shoulder.  Sizing die adjustment accomplishes this.  Even if sizing to headspace on the rim, one should still adjust the sizer for minimum 'gap' (headspace) between the cartridge shoulder and chamber shoulder.  Sizing any shorter merely work-fatigues the brass way too soon.

MZ5, I totally agree with you on this.  However, if you shoot the 30-30, one will find that once a factory cartridge has been fired, the unique roundness of the shoulder will be lost forever.  This tells me that the cartridge, FACTORY cartridge mind you, probably does NOT headspace on the shoulder but rather the rim.  When I full length resize, the cartridge never gets that roundness back and therefore I'm certain that there is minimal space between the chamber wall and shoulder area and I rarely if ever see any change or expansion in the shoulder area on my reloaded brass.  However, even when sized to such close specs, I have found that if the rim of the cartridge doesn't seat nicely in the bevel around the chamber opening and is sticking out ever so slightly, one will get over expanded cases at the web. 
My only experience with rimmed bottle necks are the 30-30 however so maybe things are different with 30-40 Krags, 32-20's, etc.

[Steve P]

Boy did this thread go south, in more ways than one.

One only has to measure rim thickness on different brands and different lots of .30-30 brass to realize you shoud size a 30-30 brass based on the shoulder location in the chamber.  ALL bottle neck cases should be sized to locate on the shoulder, EXCEPT belted magnums.  Belted magnums are sized to locate the belt (and the shoulder), but we wont go into that now as it gets really complicated.

If you were getting head separation on a full length sized .30-30 because the bullet was out into the lands, it is because of internal pressure in the brass upon firing.  Brass restricted by one or two dimensions will expand irratically.  (This is a standard practice when making wildcat brass from standard production brass.  Placing false shoulders in brass and/or bullet seating depth are used to make brass expand in certain places to create the new "wildcat" brass.  This "controlled expansion" and is more art than accident.)  Seating the bullet deeper gives you more freebore which will allow the brass to expand less dramatically.  No case head separation today, but wait for a few more firings.

I have several model 94 30-30s, several Contender 30-30 barrels, a Savage model 340 in 30-30 and I make several different wildcat cartridges using .30-30 brass.  (7x30  waters, 30 herret, 357 herrett, 6.5US, 7US, etc.) I am not unfamiliar with it's properties.  Every one of these cases should be sized to locate the shoulder directly into YOUR gun's chamber.  This is what gives better accuracy and case life.  I am not telling you that you HAVE to do this.  Only do it if you want accuracy, case life, and no case head separation.

If you do not size on the shoulder  of your brass so the base of the case is against your bolt face, the brass can move around in the chamber.  As you fire your round, the firing pin is going to contact the primer and drive the loaded round forward.  Upon firing, the case is going to expand back to fill that void.  Sizing the brass down to allow this to happen again and again is what causes head space separation.  You cannot control where the case stretches and where it sized back down.  Similar to bending a piece of metal.  If you bend it several times back and forth, it will get thinner and crack or break. If you size your round so the shoulder makes contact in your chamber, and so your case head is against your bolt face, the brass will grow less due to its restriction.  Less brass movement = better case life and better accuracy.

My 6.5 US and 7 US are both falling block actions.  I have to actually kiss the shoulder back about .001 to ensure every round will chamber.  If I don't, the slightest differentiation in the primer can prevent my falling block action from closing.  This can also be true with some .30-30 rifles.  Sometimes you have to kiss the shoulder back just about .001" to get the action to close reliably.  I found this out years ago when I was loading .30-30s for my little brother to use in a Savage model 99.  The model 99 action was a little tougher to close than the model 94s I was used to loading for.

Size your brass for your gun.  Shoulder against chamber, case head against bolt face.  Size just enough for action to close smoothly.  Anything more is excess sizing and will decrease case life and increase chances for case head separation.

Steve

[Brithunter]

Oh dear  I must say that I don't think I have read quite so much cobblers in a thread for some time 

Me I size my "High" pressure 30-30 rounds quite normally and have yet to have any case failures  when I say High pressure I mean loading a 130 grain spire point to over 2800fps. The rifle is a bespoke made bolt action and it headspaces on the rim just as the round was designed to do  .

Funny thing is that I also size my 303 British brass to headspace on the rim as well and as yet have to see a case failure on a handload in them too 

Another funny thing is that I have not noticed a lack of accuracy either  use the correct size bullet and well it goes where it should:-


3 shots of 30-30 Handload 130 grain Hornady Spire Point with H-335 powder in a Winchester case. Range 100 yards shot from a sand bag under the forestock but has no support expect that provided by my shoulder 

[Steve P]

Oh dear  I must say that I don't think I have read quite so much cobblers in a thread for some time 

Me I size my "High" pressure 30-30 rounds quite normally and have yet to have any case failures  when I say High pressure I mean loading a 130 grain spire point to over 2800fps. The rifle is a bespoke made bolt action and it headspaces on the rim just as the round was designed to do  .

Funny thing is that I also size my 303 British brass to headspace on the rim as well and as yet have to see a case failure on a handload in them too 

Another funny thing is that I have not noticed a lack of accuracy either  use the correct size bullet and well it goes where it should:

I am glad you are exempt from case head failure.  Obviously you have quality firearms without headspacing problems.  Those of us with inexpensive firearms or mass produced firearms have to deal with excessive head space once in a while.  Sometimes on more than one gun.  My method of sizing on the shoulder gives the shooter facing head spacing problems and less voluminous cash flow the opportunity to get a few more firings by reloading their brass to fit their chamber.  The information was free and you are welcome to keep a copy in your files for future reference or feed it to your recycle bin.

For those who may be confused by two different opinions on the subject, you are welcome to read an article found here:     http://www.rifleshootermag.com/gunsmithing/headspace_0612/ 
The author provides good definition of headspace and some of the particulars.  He does not go into resolutions for the typical gun owner, hunter, family man, etc.  Setting a barrel back and doing another finish ream, if possible, or barrel/bolt replacement may resolve excessive head space issues. 

If someone does have excessive head space or is experiencing short brass life due to other reasons, I hope my sizing tips help you.  If you have a custom made rifle, likely you have chamber dimensions and custom made dies so my info is useless.  Lots of guns can be reloaded and shot safely with the chamber they have.  Many thousands of American Sportsmen are reloading for field gage military Curio and Relic rifles using the exact methods I explained above.

Other readers have the same opportunity to use this information as Brithunter: file for future reference or send to recycle bin.  The money you save may buy you a Bespoke custom made bolt action in .30-30 capable of doing 1/4" groups at 100, or NOT!!   

Steve

[Brithunter]

LOL yes that particular 30-30 is an expensive bench made( i.e hand made rifle) I didn't have it made just found it at a gun show and yes it's my most expensive rifle  however there still remains the fact that I also shoot and load for several 303 rifles of varying vintages and as yet have not seen a case seperation in using them with a handload. Poorly stored milsurps ammo yes I have had cases crack and split but not with a handload.

   Now back to 30-30 one thing to watch for in undersized brass. For some reason the modern US makers don't seem to be able to make the brass cses to the dimensions that the specs call for. Winchester 30-30 brass is undersize on the rim dia, R.P 303 British is undersize in the web dimension and those are just two that I use. The R.P 303 brass I take advantage of this error to make 6.5x53R cases out of as the web area is 0.005" smaller there on the 6.5mm than the .303 is supposed to be.

As for this:-

I am glad you are exempt from case head failure.  Obviously you have quality firearms without headspacing problems.  Those of us with inexpensive firearms or mass produced firearms have to deal with excessive head space once in a while.  Sometimes on more than one gun.

Now that gave me a chuckle    I am down one 303 now having just sold it, it no longer fitting into my small collection. This carbine was a Martini Enfield AC11 converted to that spec back in 1898 by The Henry Rifle Barrel Company from a Martini Hernry IC1 made in 1888. What one would call a mass production weapon it's fair to say.

  I do have one .303 rifle that caused problems  not case seperations but the chamber was too darned tight and we could not find any dies that would size brass down to chamber, we tried 5 different sets of dies from three different makers too no avail so I had it re-chambered to .303 Improved which has sorted the prblem. Once I get the rear bridge machined down to a suitable profile so I can put scope mounts on it, Century who sporterised this P-14 cut the ears off but to what profile I cannot find out as Century refuse to answer my query  , then I can get some sights on it and start load development. So far all I have done is fire form some cases using milsurp HXP 69 Greek ammo.

  Now lets see on the 303 front there is the two BSA converted sporting rifles from the 1949-1953 period one of which needs a new barrel and a another stock due to the ravages of time and previous owners  and another BSA sporting conversion but this time on a Metford carbine action built, well we don't know on this one as it had a new 1939 surplus barrel fitted when I acquired it some dozen or so years ago. On the BSA Model E I just fitted a Redfield reciever sight and using some of the Greek shot this group:-


from prone at 50 yards

Lastly there is the Martini Muscat in .303 Bore which is of Belgian manufacture. This one has a different chamber and a tight bore with what appears to be "Rachet" rifling where one side of the land is deeper than the other so like a rachet tooth in profile. I keep some brass segregated for this one due to it's rounded shoulder rather than the tapered one the 303 should have. Finally we have a Parker-Hale sporterised No4 Mk1/2.

So thats' the current crop of 303's I am loading for others have been and gone in the past and despite there being three WW1 vintage rifles and two WW2 production rifles as I say none have caused a case seperation. A lot of which I lay at the feet of the correctly dimensioned brass which is the Greek HXP of 1969 vintage that I brought as a case of surplus ammo and shot off.

  This really made me laugh:-

and less voluminous cash flow

Oh if only you knew  I'll wager that not many members have a low fixed income like I do (just over $110 US a week) I gave up my apartment and job some 4 years ago to help care for my parents which is a full time job for me. Only yesterday Dad had a small cancerous lump removed from his arm  let's hope they got it all!

[Steve P]

It's not often that one can argue points in conversation and have a jolly good time doing it.  This is a fun thread and I thank you for the comments.

I would tell you how many 303s I have, but I do not know.  Honestly.  I have shot them all with factory ammo and even have some of the surplus greek ammo you mentioned.  My favorite load is a mild reload using the RCBS 165 Silhouette bullet as cast.  Gas check installed, but not sized. All are fine shooters for their age.  I purchased scope mounts for the different variations, but have been unable to convince myself it is ok to drill on a relic.  Mine are all originals and I have Mark Is, IIs, IIIs, IVs, an Ishapore coverted .308, one of the converted .410 shotguns, and a couple 303s made in the US.  Mine will shoot good groups at 100 yards with their open sights, but nothing like your photo.  My dad (83 yrs old) and I like to roll empty soda cans, or bust up clay pigeons.  The old war horses do their part as long as we align the sights and squeeze the trigger.  

Most of my experience with case head separations have been with Thompson Center Contenders.  Many of the barrel chambers were reamed with a drill press.  (aka tolerances suck)  I have multiples of several different calibers and have to ensure I have the correct box of ammo that matches the barrel I am shooting.  I also have to make sure I am matching my barrels to a particular frame so they headspace the same each time.  Some of the ammo sized to fit one barrel will not even chamber in another barrel of the same caliber.  I have to be especially careful with my .22 Hornets and my .270 REN as they are both using .22 Hornet brass.  Oversizing by just .002-.003" can lead to case head separation within 2-3 firings due to the soft and thin brass.  Oversizing the 7TCU (made with .223 Rem. or 5.56 NATO brass) can lead to case head separation in a couple of reloads, if pushing 140 or 150 grain bullets to maximum book velocities.   I have several tools in my shooting box that are made to remove cases that have broken off due to separating on firing.  Head is extracted and shoulder/neck piece is still in the chamber. Stick in the tool, pull out the piece of brass, and load in the next round.  

I load boxes of 100 and when I get 2-3 head separations in the lot, the brass gets tossed.  I learned rather quickly how to reset my dies after having to discard a few hundred brass.  Now I fire-form my brass for the barrel I will be shooting it in, and then load up my competition loads.  Learned to size my brass for hunting rifles the same way.  A lot of the time I will shoot less expensive factory ammo to zero in the scope and to practice.  The once fired brass is then reloaded with premium bullets as I work up to a hunting load.  The dies are set to size the once fired brass to just fit into the chamber of my guns with minimal amount of force on the action.  After about 4 firings, I usually have to do some trimming and reset the dies to push the shoulder back about another .001-.002".   Depending on the manufacturer of the brass, I may also do some annealing.  (military brass for sure after about 4 firings.)

Well, another novel written on a more popular debate issue.  I wish you and your parents the best.  I hope your Dad recovers from the surgery and all goes well.

Merry Christmas and Happy Holidays to you.

Steve

[Brithunter]

Thanks Steve  I will pass on your good wishes.

The surgery was minor and done under a local which is lucky as a full knock out job is dicey at his age and health. Dad is 86 now and has had several strokes over the years this is just the last thing they have found. Too much tropical sun from WW2 in the Far East  .

Have a wonderful Christmas and new year  .

[Autorim]

I have been following this thread and will throw in my 2 cents worth. I keep my bottle neck brass and loaded cartridges separated for each rifle and size only enough to properly chamber. Yes, I have more investment in sizing dies, but it is affordable. Also, brass that is used for low pressure cast bullet loads should be kept segregated and never used for more powerful loads. With low pressure loads, the shoulder can actually be set back slightly by the firing pin blow and create excessive headspace that will not be touched by the sizing die. If such brass is then used for full power loads, a case separation is very likely.

All of my rifles are bolt action or Ruger 1 or 3 single shots so action spring or flexing is not an issue.

Ken