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Discussion Starter #1 (Edited)
This was an important and instructive thread. Due to some little responsible comments in such a safety-relevant matter, it would however have demanded heavy moderator invention ("Dutchman style" ;-) ), which was lacking at the time. It is I who now appropriately edits this thread while importing it.

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cannonball3a
Germany
269 Posts
Posted - 06/30/2007 : 1:46:34 PM
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Gentlemen. Although I don't have any Swedish arms I need your help. My polish friend Jazek joined our session on an open military range today. He was shooting his M 38. Suddenly his gun literally desintegrated into woodsplinters and steelfragments. The bolt was found 15 meters behind him, crossing a bunch of spectators on his flight. Part of the foreward ring and the bridge couldnt be recovered, maybe they are passing ISS right now. The case still stuck in the barrel, casehead ruptured off. His little finger on his left hand, supporting the stock, was allmost cut off his hand. Thank god I am always carrying my military first aid kit when on the range.

How could this happen? He was loading 37 gr of Kemira N140, a medium burning powder. I dont think he could double the charge.
Do you know of similar accidents?

BTW, he was complaining about the loss of his rifle, not of his finger. We suggested he could celebrate a second birthday every year. The allmighty must love polish shooters.
Wolf



Big commander
Belgium
967 Posts
Posted - 06/30/2007 : 9:35:49 PM
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What was the weight of the bullet? Could the bullet got inside of the case? To give just one example, I've had a M38 that shot perfectly with 33,7 grains of N140 with a 144 grains Lapua bullet. Did you see the already shot cases (before the incident) and how are the primers of these? There are so many questions that could be asked but ... there is always a reason that those things happen. Worn cases, bad reloading techniques, head space problems etc.
Such accidents are always spectacular and I am sorry for your friend. I hope he reloaded himself his cartridges! Was the person, himself or anybody else, who reloaded the cartridges experienced? I reload for some 40 years and don't mind to be a mentor for the novice but always refused to make cartridges for somebody else.



JIMMYC
Posted - 06/30/2007 : 9:36:20 PM
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Sounds like a classic overload situation. If the bore had been blocked the barrel probably would have burst instead of the receiver letting go. I checked my reloading manual, and found the largest load of a 6.5x55 to be 55 grains of H450. So with your friend only loading 37 grains of powder would leave almost enough room for a double load situation. Did the bolt lugs fail or did the bolt come out of the receiver because of it's failure?? I would assume the lugs didn't fail or your friend would be sporting it in his forehead!!



Big commander
Belgium
Posted - 06/30/2007 : 9:47:48 PM
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I am afraid that JimmyC is right.



cannonball3a
Germany
269 Posts
Posted - 07/01/2007 : 04:01:42 AM
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To answer the questions: The barrel was in perfect shape after the incident, the locking lugs were ok, only the extractor claw was bent away. He loaded his ammo himself and the cases, he fired prior to the detonation, showed no signs of overpressure.
I think it was an overload situation, because he throws the powder directly from the powdermeasure into the cases. It sometimes happens, that powdergrains jam the funnel in the midth of a throw and let go on the next throw. So he might got an 50% overload. Thats why I myself put every charge on the scale.
Wolf



capnduane
Posted - 07/01/2007 : 10:56:26 PM
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I have never liked powder measures....... Can't really see whats goin on. I use Lee dippers and my powder scale. But then, I'm a hunter, not a target shooter, so I don't load/shoot all that much. Once all the cases are charged, Then under a strong light, and a visual check of the powder level in all cases before seating the bullets.



cannonball3a
Germany
269 Posts
Posted - 07/02/2007 : 12:25:24 PM
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capnduane, you are absolutely right, best available safety instruments are your fingers, eyes und brains. But Murphy was right too. The doorbell or the phone rings, wifey cries "ready for lunch", kids are squabbeling and voila... you are distracted. Happens to me, that I forgot to charge a complety line in my loading board and, after 4 missfires, had to shake 996 cartridges to find the empty ones.

And I started reloading 1979 at the Fort Bliss rod and gun club and guess I am pretty carefully. But afterall I am only a man and unable of multitasking operations.



jorma
Finland
548 Posts
Posted - 07/04/2007 : 08:47:24 AM
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Hello gentlemen, it would have been an underload detonation as well, my english isn`t good enough to explain that, but I think you can find out. Using you eyes after charching
powder in the case will prevent both under and overloads.Happy and safe shooting.
Have seen some rifles sent to Sako for gurantierepair, one have reseiver cut after the
locking lugs foreend of stockcutoff and barrel dropped to ground, brasscase melted like
butter and between bolt and receiver. All mistakes made what anybody can do oversize bullets and too fast burning powder, so it`s very vise to ask from pros if anything
starts bugging you and you are not sure what to do.
rgds jorma



Mike442
Posted - 07/05/2007 : 02:10:21 AM
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Hi wolf,
Sorry to hear about your friend, but as already stated, he is very, very lucky it wasn't worse. I agree with you, it might be possible that he got a 50% overcharge using the powder measure as you described. I find it hard to believe that a 6.5 x 55 case could be double charged using 37 grains of any of the medium burning rifle powders. The case just isn't that big. However, none of my reloading manuals list the Kemira N140 powder for this cartridge, and even though I have been reloading for over 50 years, I am not familiar with that particular powder. My favorite load (most accurate) in my M96 Swede is 36 grains of IMR-4895 powder behind a Sierra 140 gr. SBT bullet. This amount of powder fills the case to just under 70% (so there is no way to double charge). Also, I always measure out each charge on a scale. I don't use or like powder measures for numerous reasons.

Capnduane also brought up an very important point, and something that I have always done, and that is to visually check the powder level in all the cases under a good lighting source before seating the bullets. Any "major" powder overcharge/undercharge problems or any completely missed cases will immediately become apparent. It's a very good practice to get into if you are not already doing it. As you already stated above, there can be many different kinds of distractions during a reloading session, and visually checking the powder level just before installing the bullets is additional insurance that no "major" mistakes were made.

Hope your friend has a fast and complete recovery Wolf. Shooting and reloading is a great hobby and I really hate to hear about any of our fellow hobbyist getting hurt. Very unfortunate for everyone.



jorma
Finland
Posted - 07/05/2007 : 09:55:48 AM
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Hello Mike in front of me is loading manual by Vihta Vuori and it recomends N140 for bullet weights from 77 to 130 grains. The manual is from 2002 but you can find more update info from www.vihtavuori.fi



Mike442
Posted - 07/05/2007 : 8:04:02 PM
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Thanks Jorma for the info. I've had very good luck with the 6.5 x 55 Swede using the IMR-4895 and H4895 powders with the 140 grain Sierra bullets and Lapua cases, but I have never used the N140 powder and may try it sometime. However, what works well in one rifle may not do so in another.

You mentioned the bullet weight range used with the N140 powder. I wonder what bullet weight Wolf's friend was using. I don't believe he ever said. But it really doesn't matter since 37 grains of N140 would not have caused this kind of accident even if using the heavier bullets. Inspection of the reloading data (even though it doesn't list the N140 powder for bullets heavier than 130 grains) shows that 37 grains would not have grossly overcharged the cartridge even with the heavier bullets. Especially when you consider that rifles are designed and manufactured with a minimum 2 to 1 safety factor.

Of course without an in depth forensic analysis of the rifle and cartridge parts, no one can say for sure what caused the accident. However, such an analysis would be expensive and time consuming. Probably why the real cause of such accidents hardly ever comes to light, except when serious injury or death is envolved and a law suit ensues.

But based on the information given, my first guess (and that's all it is) would fall into three possibilities (and I'm sure there are many more):

1. Rifle defect - Since examination of the barrel and bolt showed no signs of damage, I would suspect improper heat treating of the receiver, a cracked receiver, excessive headspace, or any other number of receiver issues that could have been the cause. However, this is highly unlikely.

2. A gross powder overcharge - Based on the statements regarding the use of the powder measure without verifying the weight of powder dropped could have resulted in a gross overcharge. Much more likely than item 1. A double charge would be highly unlikely, since I don't believe 74 grains (2 x 37) of any type "rifle" powder could fit inside the volume of a 6.5 x 55 Swede cartridge case.

3. The "squib" load - Although there did not appear to be any damage to the barrel, just the pressure generated by a primer with no powder in the case could have pushed the bullet into the barrel just far enough to allow the next cartridge to be chambered. Especially if the bolt was forced forward with a lot of force and the additional camming action of the bolt lugs completed the job. Peak pressure build up at this point in the barrel (where it is largest in diameter and strength) may not have resulted in any visible or obvious damage to the barrel. Especially if the bolt thrust (rearward force on the bolt being transferred thru the lugs and into the receiver) failed the receiver first. The weak link in the chain always shows the most damage when failure occurs. This scenario seems the most likely to me. It is real easy to miss charging one case among many in the reloading tray. That's why it is so important to visually check the charge in the cases before seating the bullets.



cannonball3a
Germany
269 Posts
Posted - 07/06/2007 : 12:34:33 AM
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Mike, I dont know the exact bullet weight but it was the usual FMJ type. We are shooting on military ranges with a steel lamelle backstop and 10" of selfsealing plastic in front of it ( to prevent ricochets). Other bullets than FMJ would damage the plastic when passing through. My friend is a tough guy, after taking care of his finger ( we didnt found his missing tip eather) he continued shooting with his Carl Gustav and the same batch of ammo without any problems.
Wolf



Mike442
Posted - 07/06/2007 : 01:33:18 AM
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This is off the subject, but just thought I would mention that my two boys and I are planning another trip to your country in April. My oldest boy speaks German and visits there quite often, sometimes for six months at a time. He travels all over and has friends in both Berlin and Freiburg.



jorma
Finland
Posted - 07/06/2007 : 04:12:54 AM
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Mike if you are using 140 grain bullets you have to use N150 OR 160 POWDER OR RELEVANT.
Chek the loading data before bying any powder that is very IMPORTANT.



Mike442
Posted - 07/06/2007 : 1:54:36 PM
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Thanks Jorma. Yea, when I wrote my response it sounded like I was going to use the N140 powder with a 140 grain bullets. I should have been more clear and completed my sentence as follows: "but I have never used the N140 powder and may try it sometime" with the lighter bullets.
 

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Discussion Starter #2
Wolf, you ought to be aware that *several* accidents with m/96 (and or occasionally with m/38 or the so-called m/96-38) have taken place among German shooters. This has little to do with the quality of the guns, but rather with the simple fact that the Swedish Mausers are the single most popular guns for non-smallbore sportive rifle shooting here, so the high number of guns reflects more accidents than with rarer guns, as simple as that. One must keep in mind that the majority of accidents never come to the cognizance of administration or experts and are not published either, unless somebody is severely hurt or killed.

1. The present German fad - almost universal here - of concocting light loads with a fast powder such as Vihtavuori's N 110 or N 120 is due to the match regulations (40 shots in limited timeframe), which definitely advantages these propellants (less recoil, less barrel heating). These loads however are not ideal from a safety perspective, for two reasons:

a) Accidental double charges are possible.
b) Uneven pressures due to low loading density, depending upon where the powder was positioned when the striker hit the primer.

2. A barrel obstruction with otherwise correct gun would lead to barrel damage (often but not always a blown or longitudinally split barrel), would create very high pressures, and would leave according traces on bolt head and according damages. None of these seem to have been present, following Wulf's description.

3. The allgedly intact, undamaged (?!!) bolt lugs are a dead give-away here. If they were neither deformed nor cracked, then it is clear that extreme cartridge overpressure was not the culprit. The cartridge bottom would of course be the more importance source for pressure assessments.

4. The style of specific damage shows the immediate cause of the blow-up: massive gas escape from the case into the receiver ring.
This however need not necessarily be due to overpressure (which could be either obstruction-induced or propellant-induced).
Actually, the description sounds more like a case failure due to a case flaw. And the single most likely cause for this latter is exaggerated shoulder setback during case-forming. The cartridge case is thus lengthened with each shot and continuously thinned near at the bottom. I believe this may have been the cause here. Only a forensic expert could tell more.

Carcano (one of the safest rifle actions around!)
 
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