Guys, I have a serious question today. After 28 years of reloading and 42 years of shooting, I experienced my first ruptured case today. It was in my brand new Chapuis 9.3X74R. Here is a picture of the case:



Details: Hornady brass, 53 grs of IMR 4064 (Max Load according to the Barnes #4 Manual), 286 gr TSX bullet. This was the first firing of this piece of brass. Second trip to the range with the rifle. I started at 49 grains and worked up to the max of 53 grains, 1/2 grain at a time. Chrony showed average of 2217 fps while the book shows 2237 fps. The primer looks fine with no cratering, flattening, piercing, backing out, or pocket expansion.

This shot occurred out of the right barrel on shot #59 out of 60. We did not realize the case had ruptured until after firing the left barrel and ejecting the cartridges. So in fact, this was shot number 30 out of the right barrel and the 19th overall shot (counting both barrels) at the 53 gr. maximum with no other cases showing any signs of problems.

What really scares me is that my son was shooting the rifle when this happened. It was his 3rd shot with the rifle. He says it felt like more recoil than the other shots. The Chrony showed 2209 fps for this shot.

Any help would be greatly appreciated. Let me know if I've left out any additional data that might be helpful.

Todd

Todd, It is possible that the brass was insufficient at production. If none of the other cases show the same expansion areas on the brass, I would load the same load again and try it in the right barrel again. If it doesn't happen again for 5 rounds, I would assume that the brass was thin already. New Brass or not, they make mistakes also. If any of the 5 rounds you load and shoot in the right barrel do the same thing, I might suspect a misbored chamber or very loose at the very least.

When I got my Chapuis several years ago I had complete seperations several time using Norma brass.It always started about where yours did just above the rim. From what I've read Norma's added brass since then.
I've never had problems with any other brand before or since.
Call it a fluke but procede with caution for a while!

First thing I would do is to get out the dremel with a cut off blade and slice the case in half lengthwise. Visually inspect the case to see if it was thinner in any area. Might give you a clue as to what happened.

I have had case head separations with Norma brass in my Chapuis but never a rupture like you have.

Could be the brass was very undersized and expanded more than normally. Other than thin or undersized brass I can't be of to much assistance.

The suggestion to keep on firing in the same barrel seems to be a good one. If it continues to rupture in the right barrel and not the left you can rule out faulty brass.

I'll section a couple of pieces of brass and compare it. I think I remember the threads concerning the Norma brass. Don't recall anyone having this issue with the Hornady brass.

Unless someone else comes up with something more definite, I think I'll back off the load by a couple of grains and not let my son shoot it again until I get confidence back into the gun and load.

Possibly too much back pressure? You know my feelings about the Barnes bullets. Just consider this.

Yeah Mike,

I understand your position about the TSX. I really don't think that is the issue here. Could be, but I don't think so.

I'm leaning towards a fluke but will continue with caution until further info becomes available.

This is the first time I've ever seen a separation like this. I've heard of them but usually because someone put a 270 Win in a 270 WBY Mag or similar. How common are these things is my question. I've been at this game over 40 years.

Other than the Norma problems it's never happened to me before either.
Section them and take a look. It's probably a fluke.

I might have a few more years at it than you but not many.

Todd, After several case head separations with Norma brass and a couple with Hornady I started neck sizing only. (I do that with all my other rifles; it just didn't enter my feeble mind when I started shooting my Chapuis.) Now I get 5 or 6 shots out of the brass before I start to see a ring forming. From what I have learned a lot of the European doubles in 9.3 x 74 are made to the upper end of spec on chamber size to make sure every round will chamber and fire. I have the Cerosafe sitting here to make a cast of my chamber but haven't done it yet. Norma is supposed to start shipping their thicker and larger brass sometime after the first of the year. (They started production of the brass this summer but so far it is only shipping in loaded rounds.) I agree with the other guys that you probably got a thin piece of brass. Out of my first 5 boxes of Hornady brass I had one that was deeply corroded so I guess a bad one gets through every once in a while.

Todd: Have you measured the fired brass from the left and right chambers? Are the readings the same?

Bill, I have not, but will today.

Who makes Hornady brass?? Norma??

DM

This was virgin brass? Did you FL resize before loading?

Hi Antlers,

Yes this was virgin brass straight out of the box. I did FL resize before loading as well. Any ideas?

I had a case split vertically in a bolt rifle.I don't know what caused it but it was new factory Winchester ammo.One thing that was remarkable was the poor accuracy with it.Bullets sprayed a foot to two feet apart at 100yds.I switched to Remington ammo and the rifle returned to shooting very tight groups at 100.Did you have accuracy issues with your loads in this particular rifle? If so,I would change my brass and maybe, powder.I had two other rifles that responded negatively to a particular brand of brass again spraying bullets,and the issue was instantly resolved when I changed the brand of brass I was using.

Cases often split in several areas and these splits can be an indication of several things.
Split case mouths or necks often indicate work hardened brass from multiple reloadings. Annealing will often correct this issue
Split cases or case separations near the base or rim are typically due to the brass stretching after multiple reloads and can sometimes be minimized by neck sizing only. In my experience belted cases work best with neck sizing. Flanged cases often used in a double rifle should always be full length resized IMO. I like others have had problems with Norma brass separating in this area after one or two reloads. Had it happen in my 470 and 9.3x74r on more than one occasion. Other brands of brass don’t seem to be a problem in my doubles.
A vertical split that forms a straight line crack can be a sign of chamber or head space issues. I have seen them most often in military semi auto rifles from the WWII time frame. It is my believe that some of them were the result of slam fires since the problems I witnessed were not consistent.
The photo above shows a case that split in a somewhat curvy line. I believe the case was bad from the factory. It probable has a fold in that area and was weakened in the production process. I expect the case should have been culled from the factory. I see no signs of excess pressure or chamber issues.
I would inspect all the brass for similar issues but expect that you simply got a bad case. I would guess that Hornady would gladly inspect the case for you and possibly replace is with a new box of ammo for your trouble.

Like Roscoe and others, i'd put my money on a bad case that slipped through QI.

Though it has been fired and has powder residue in it, what does it weigh compared to others from the same batch? If you ahve another lot number of brass, it would be interesting to see what it weighs compared to those.

I would give Hornady a call ( they have always been excellent with me when I have called with questions). Let them know what has happened and how they would like you to proceed. You may make out well on the deal but if nothing else, letting them know there was a problem may prevent it from happening to you or someone else in the future.

Stay well,

Paul

I don't think any ammunition manufacturer, especially an american one, makes cases that are faulty and dangerous.IMO,it is not a defected case.Imagine they made bullets that lodge in barrels etc...

Thanks for the info guys. Bill sorry I didn't get to measuring as I realized that all the brass from that group of 20 has been mixed up. Can't separate the L from R. I'll need to load some more and go back to the range.

Thank's for the insight Roscoe and Doc. I do have other batches that I can weigh. I'll give Hornady a call today and see what they say. Not looking to get anything from them in any way. I just want to know that the loads are safe to proceed.

Thanks again for the comments.

You might try weighing the brass to see if any are light.

I weighed a large sampling of the 60 fired cases along with the split case. They are all within .3 grains of each other with the split case being right in the middle. Of course, these cases have been fired and have varying amounts of powder residue on them so I think this measurement is indicative of the cases being uniform weight wise.

I also measured just above the rim and found them to all be within .001 of each other, including the split case. Actually, my micrometer only measures to .001 and there were no cases that varied by this amount. This would seem to rule out any issue with the chamber or pressure to me. By the way, Ken from Kebco called me this morning to discuss the case rupture as he saw this thread. I have to say that Ken is a first class guy and runs a first class business. I bought this gun from him and it certainly will not be the only gun we do business on.

I can only think at this point that there was a defect in the case itself. I'll go ahead and contact Hornady as I'm sure they would be interested in knowing about it. I would if it were my company! Not looking to get anything from them however.

I appreciate the responses and insights. I'll certainly report back if Hornady provides any additional info or if it happens again.

Todd,

I agree, Ken is all about making the customer happy and doing the right thing. It seems that your due diligence has essentially ruled out a chamber issue since there is no significant variation in post-firing case dimensions.

That leaves only the case itself as the cause. It will be interesting to learn what Hornady folk have to say.

Good luck

Shootaway, I don't think I answered your question. Sorry about that. All shots seemed to display very good accuracy. There were a couple of shots pulled as always but all shots executed properly hit the bullseye.

quote:

Originally posted by ROSCOE:
Flanged cases often used in a double rifle should always be full length resized IMO.

Roscoe,
After a couple of case head separations in my Chapuis with Norma brass I started to change the way I resized cases and adjusted the FL resizing die down in small increments, resize, and see if they would chamber. Once they would chamber would lock the die in place. I also became extra paranoid about case head separations and will only use new brass on a hunt.

Why do you suggest FL resizing?

I may be all wet in my rational….but the basis for my comment on FL resizing is as follows:

1. On a double you have two different chambers. I have never had any indication of any major discrepancy between the chamber dimensions on my doubles, there is no doubt that there will be some variation. FL resizing eliminates the potential for the variations to cause problems with ammo not fitting the chamber. I have seen some people segregate brass when they reload….meaning Left always stays left, and Right always right. To me I play it safe and size them all to factory specs.
2. Serious problems can occur if the case does not fit completely into the chamber on a double. Butch Searcy always stresses to look at the position of the lever on an empty rifle. Once loaded, the lever should be in the same position. If it is not then do not fire the gun as it can cause problems with the gun wearing the locking lugs, which can cause the gun to open when being fired. Bullet seating depth, proper improper sizing of the case, and improper crimping of the bullet are common errors that can cause the reloaded cartridge to not fit properly.
3. I primarily use my doubles on dangerous game. As a result I try not to take chances on anything that can cause the gun to give me problems while hunting. Simply stated, FL resizing is a safe play IMO even though it can reduce case life in some rifles. I think with good brass, premature case failure is not very prevalent.

These ideas are my own and I don’t claim to be an expert on the subject. I would be interested on hearing any opposing views.

All valid and good points.

Did not give any consideration to the dual chambers. But being a cheap ass I am always tring to get as many loads out of a case as possible. Might get bored this winter and see how many reloads I can get out of FL resized brass compared to partial FL resized.

Never paid attention to which case was fired in the right or left barrels. But now I will make sure all the rounds will chamber in both barrels before going to the field.

I still stay with new brass for hunts. Might be overkill but makes me feel better.

One thing for certain, seems more people see split cases in the 9.3's than anything else.

weak brass.

Mike

Do any of you guys have any experience re-loading Federal brass in 9.3 x 74? It isn't currently available as a component so it would have to come from fired factory rounds. In some other calibers I have noticed it seems pretty heavy. Or, since it is a European caliber is all 9.3 brass made to CIP specs?

Over the 40 plus years I have handloaded ammo, I have had a few ruptures like the one pictured. They were generally on the first firing of the brass. Mine were all in bolt rifles. Since I weigh each powder charge and visually inspect before seating bullets, I attributed the failure to a defective case that slipped thru. I don't remember the instances being limited to one manufacturer either. I generally used either Remington or Winchester brass until I started loading for doubles.

I contacted Hornady about this case and sent them the picture of it last week. Haven't heard anything from them yet.

Plan on starting over tomorrow and working my way back up to the Max load again as it matched the test target. I'll report back on how the shooting goes and if I hear anything from Hornady.

All good practices posted here, and here is one more!

When I buy a double rifle there are a few things I do automatically! First is deciding the extent I want to size the brass, and to do this If available I buy one box of factory ammo. With this box I dump all the cartridges out of the box and try them one at a time in both chambers to see if the fit both chambers with a drop-in chambering! If this is the case, and usually is, now I fire one round in each barrel to fire-form the two cases.

Now I reload each cartridge keeping track of which barrel each was fired in. I do not re-size other that just enough on the neck to hold the bullet. Now I place the right in the right chamber, then in the left chamber, then reverse them with the left in the right chamber and right in the left chamber, if they are both drop-in chambered I will only neck size there after!

If however one is a little sticky chambering I will size just enough for the smaller chamber. Now I mark these two lft and rt and use as die setting dummy guides to adjust my dies for that rifle so all loaded ammo will drop in either chamber!

The above is only necessary if you have several double rifles so that you have a guide dummy for each rifle on your loading bench! This may sound like a lot of trouble and picking the “fly shit out of the pepper” but you only have to do it once per rifle, and if I have two rifles of the same chambering I mark the dummy rounds for the rifle they were made for, and place them is the case with the rifle as well!

In any event to avoid some serious mistakes all ammo once loaded must be drop chambered in each barrel before boxing it up to go buffalo shooting! As Roscoe says the last thing you need is a double rifle that fails to close properly on a re-load in the middle of a fight with old Black Death!

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I use only new brass to hunt DG..I try each round in both barrels prior to the hunt. Never had a problem so far if I did this..Have had from not doing it.

On ocassion if you do not full length resize double rifle brass it will be tight to chamber so again all rounds must be tried in both barrels.

I would check to be sure my double was on face first of all, then if it is I would perhaps check the headspace just to be sure, but if its on face the headspace should be OK, but won't hurt to check..A double can go off face with a single shot the is too hot. Why the case is split is anyones guess..I would not be too concerned over one incident but if it happens again then I would chamber cast that chamber and consider returning it to the dealer for inspection...I think it had a seating problem based on the dark back area of the case and that could indicate several problems such as an oversize chamber perhaps..hard to analize a problem on the internet with a single picture.

Fired 60 more rounds through that rifle yesterday, 30 in each chamber/barrel. No issues with split cases. So I am assuming it was a bad piece of brass. We'll see how it goes into the future!

I've had only a couple of longitudinal splits over the years...a few head separations...all with bolt or single barrel rifles...and all the longitudinal splits were sectioned and found to be thin, faulty brass...you could have probably dented it with your thumbnail if you knew where the fault was.

For a long time now I've been fitting my sizers to the various chambers by polishing it out as to end up with ~0.002" resize on the base and about 0.001" on the OD of the shoulder or as close as I could to those numbers...even with my straight walled cases.

Once you establish the actual amount your die resizes and the difference between the barrels you might consider doing the same thing...at least matching as close as possible.

The only times I ever had a sizer match right was with reamers I had made and I cut the chambers, then sent 3 fired cases to a custom die maker...factory matchups are a crap shoot at best.

There shouldn't be more than .001" difference between the two barrels I would think, or am I wrong in guessing the barrels were cut with the same reamer???

I don't have a double or much knowledge about them as a whole, but matching the sizer to the chamber has alwasy worked for me in reducing the amount of work sizing and in work hardening the brass.

I loaded one 444 M case 40 times including expanding for lead bullets and crimping, while developing loads and through the chronographing AND to answer some questions...I went another 20 odd firings on anouther case until I quit counting.

These were fired in a Marlin 336 levergun at normal 444 M pressures ~42-45KCUP and the only thing I could find "wrong" with that 40 rounder case was the case walls had thinned by ~0.001", primer pocket was still tight and the case had stretched ~0.001" per firing.

I've gotten as high as 12 firings from my belted magnums doing the same thing. They might have gone more but 12 was my "safe" limit.

Might be something for you to consider.

Luck

Don't have my loading books here, but what is the charge density for the load you were using? It looks like the separation occured at the front of the web, and the web section looks like it was expanded outward completely, from the crisp look of the head section sides. It could have been some form of a detonation due to the charge being in the front of the case. The normal working pressure of a 9.3x74 is in the range where this has been reported over the years by many people using relatively light charges in a large case. It's controversial, and a lot of people don't believe it happens, but it has been reported commonly for the last 50 years or so. I would have thought that there would have been other pressure sign if this occured, but am just pointing it out as a possibility.

I have only had two case problems in the last 50 years; one in which a 280 case destroyed itself for no reason with a reduced load of 4064, and one a new 300H&H case that looked exactly like you case (complete with no primer damage or case expansion) when fired in a chamber with an extreme headspace problem.

quote:

Originally posted by Art S.:
Don't have my loading books here, but what is the charge density for the load you were using? It looks like the separation occured at the front of the web, and the web section looks like it was expanded outward completely, from the crisp look of the head section sides. It could have been some form of a detonation due to the charge being in the front of the case. The normal working pressure of a 9.3x74 is in the range where this has been reported over the years by many people using relatively light charges in a large case. It's controversial, and a lot of people don't believe it happens, but it has been reported commonly for the last 50 years or so. I would have thought that there would have been other pressure sign if this occured, but am just pointing it out as a possibility.

I have only had two case problems in the last 50 years; one in which a 280 case destroyed itself for no reason with a reduced load of 4064, and one a new 300H&H case that looked exactly like you case (complete with no primer damage or case expansion) when fired in a chamber with an extreme headspace problem.

Load density is 96%. Don't think there is a headspace problem. It's a brand new rifle and has now had 120 rounds fired through it. I haven't had the headspace checked but wouldn't there have been issues with the other rounds if this was an issue? This is the only one that had a problem. There are no other signs of pressure on this case or any of the other cases I've inspected.

Ray, the rifle is on face. It's brand new and I've fired all the rounds through it other than regulation. All rounds were worked up from the minimum load to max, checking for pressure signs along the way. No pressure signs were found except for this one case rupture. Even this case measures the same as the others above the rim, shows no issues with the primer or primer pocket, and the velocity was captured on my chrony as being right on the average of all the other 60 rounds fired in those first 3 boxes. This rupture happened on round #59 overall, #30 in the right chamber. To my knowledge, it hasn't experienced "ONE" high pressure shot to take it off face. Also, this was a brand new case on it's first load.

FOOBAR, that's a bit more trouble than I'm willing to go through with a rifle. If it requires all of that, I'll sell it.

Pretty sure it was just a bad case at this point but it would be nice to hear something back from Hornady. As a side note, I reloaded the remaining 19 cases from that batch. Each was full length sized without undue effort being necessary. Just a fluke I think.

Hardly any trouble at all...takes me about an hour to do the whole process from firing the first round, miking, polishing with a piece of 320 wet/dry wrapped around a brass rod in a drill motor with the die in my lathe, firing and checking a few rounds, to finish polishing with 600 wet/dry. A gunsmith might do it faster by using diamond dust.

Doesn't matter...most likely just one bad piece of brass and it won't happen again.

Luck

quote:

Originally posted by FOOBAR:
Hardly any trouble at all...takes me about an hour to do the whole process from firing the first round, miking, polishing with a piece of 320 wet/dry wrapped around a brass rod in a drill motor with the die in my lathe, firing and checking a few rounds, to finish polishing with 600 wet/dry. A gunsmith might do it faster by using diamond dust.

Doesn't matter...most likely just one bad piece of brass and it won't happen again.

Luck

I'm sure it is easy once you know what to do, but it sounds a bit over my head!

Apparantly it was faulty brass it would not concern me any further...

On double rifles I file the expander ball to give me a snug bullet fit, usually cut off and polish .003 or a bit more sometimes then use a high density powder to ever so lightly compact the load when the bullet is seated usually H or IMR4831, then a very light crimp on file trimmed brass to keep the crimp the same from round to round. If I have air space in any double rifle load I add a filler, Kynoch plugs are cheap and best but about 5 grs. of Dacron works well enough.. Brass last a bit longer if you do these things. I have seen too many double rifle cases have head seperation in the fiek to feel insecure about it..I carry a 45 caliber brass brush on a small homemade handle, stick it in the chamber and it grabs the headless case and pulls it out easily..problem solved.

For what it,s worth, I always hunt DG with new brass hand loaded. Double rifle brass is on the tender side compared to bolt action brass. I seldom load a double to max, I see no need as those big bores kill by knocking big holes in animals and velocity within reason is not a factor in killing effect, by that I mean 2100 FPS is as good as 2400 FPS as far as I'm concerned with 40 caliber and over. I cannot see that my 404 or 416 at 2400 FPS kill any better than my 4540-400-3" does at 2125 FPS, it simply doesn't.

It's no big thing...fire a case, mike the top and bottom, size it, mike the top and bottom...it there isn't much more than a couple thou' difference at the base between the two measurements, I wouldn't worry about it as you DON'T want a tight case in a double if things get sticky.

I've come across 0.008" difference in a few chamber/die dimensions, basically a maximum chamber/minimum die and the other way around...manufacturing tolerances in both the chamber reamer and the die reamer. A fat chamber and skinny die can be fixed easily enough...the other way around and you need another sizer or a rechamber.

It there is over 0.003" difference, ANY gunsmith/die maker can adjust the die if you send along 3 fired cases and tell them it is for a double rifle...although, again, I'm not familiar with what is considered tight/loose in a double. This is what I do even for my T/C and NEF single shots and haven't hit any snags with just dropping in a round and closing the action.

You said you have no problems sizing so I would suspect that the die and chambers are well matched...maybe I shouldn't have mentioned it...it is something I do as a matter of course because I expect 1/2" groups or less from my rifles...for 3 shots minimum in the mediun to heavy cals and 5-10 in the varminting cals.

After having the second split case I started using once fired, FL sized cases in all my rifles except my varminters as far as hunting goes...that way I would eliminate(hopefully) any problems with longitudinal splitting. Plus once fired cases along with fitted sizer gave me the best possible worlds as far as accuracy/pressure was concerned...everything fits.

The brass cost is chump change compared to the rest of the hunt costs. I mark each case with a magic marker each time it's fired so I know at a glance when the cases are getting close to "EOL"(End of Life").

I thought about doing a 9.3x74R switch barrel for one of my NEF receivers, but that thin rim made me uncomfortable so I did a 9.3x62 Mauser instead. The closest I can get to a double rifle is my own reloaded slugs ala Ed Hubel in a 12ga double barrel... and they seem to get the job done well enough.

Luck

Luck