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  1. #46

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    I haven’t read every post on this string so if what I’m adding is redundant, I apologize. I’d be curious to know if the rifle was being single shot or if the magazine was loaded up in which case was the neck tension/mild crimp sufficient to keep the magazine loads from having their bullets seat deeper from recoil, which makes little bombs. Ask me how I know.

  2. #47
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    Split base in a Remington 700....bit of smoke ......split base in a 96 Mauser (or any pre 98),kaboom,reciever burst ,magazine blown,wood splintered .......Simple reason is all the 96 clones (1903 Springfield ,M17 included) rely on the case base to hold chamber pressure.....Section a case and see how thick is the failure zone from interior to rim recess.....Not much brass.

  3. #48
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    Quote Originally Posted by maxfaxdude View Post
    I'll probably catch hell for saying this. But this is why I NEVER shoot handloads or reloads!
    Reloads are a two-edged sword. Admittedly, as illustrated in this very informative thread, carelessness and/or lapse of attention can have catastrophic results. But on the other hand the reloader can inspect every component used and control every stage of the process.

    Mass-produced ammo cannot possibly have as thorough and conclusive quality control as hand loads. That, of course, depends upon the reloader and effort and attention to detail he cares to invest in his work.

  4. #49
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    Quote Originally Posted by coktnlokt View Post
    I haven’t read every post on this string so if what I’m adding is redundant, I apologize. I’d be curious to know if the rifle was being single shot or if the magazine was loaded up in which case was the neck tension/mild crimp sufficient to keep the magazine loads from having their bullets seat deeper from recoil, which makes little bombs. Ask me how I know.
    See my post #48.

    Checking neck tension is one of those quality control checks I alluded to. With a hand press, you can feel the force needed to seat the bullet. If I feel that the bullet went in with less resistance than the rest, it gets culled.

    I use the Lee factory crimp die for ammo I reload for my AG42b and Garands, both 30-06 and 6.5x55. The force with which a self-loader chambers a round can also cause set forward, where a bullet can move forward out of the case neck under inertia.

  5. #50
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    If this is the same one I saw, he later stated he instead of using the IMR 4350 which has a purple label, he grabbed the IMR 4198 which also has a purple label
    We sleep safe in our beds because rough men stand ready in the night to visit violence on those who would do us harm _ George Orwell

    "You see in this world theres two kinds of people my friend. Those with loaded guns, and those who dig... You Dig" Blondie from TGBU

  6. #51
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    Quote Originally Posted by Leon View Post
    It's not "Stewbaby"; he is only reporting another incident.

    Close up photo shows the action is a Carl Gustaf. The receiver ring was drilled and tapped for a scope mount. I think this may be significant.
    I am not an expert by any means on gun smithing and D&T work. I do know that receivers are typically surface hardened. This makes drilling very difficult, so the gun smith has to anneal - soften - the surface area to get the drill bit to dig into the metal. It is possible that the annealing procedure weakened the receiver ring. Again, this is conjecture on my part; folks with actual experience need to join in here.
    I didn't know that receivers are surface hardened. If the gunsmith had to anneal the area then I'd say that would have contributed to this failure combined with maxing out loads...
    Then again I'm no expert, just a mechanical engineering student.

  7. #52
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    Not all receivers are surface(Case) hardened. The example here is. After working on guns for 40+ years, I have learned to ask "Do you reload?" before attempting to repair something. My first thought was overload or wrong ammunition. A controlled feed bolt will pick up a shorter cartridge and fire it. It takes a lot to have a break up like that. Nothing wrong with reloading, but you have to be careful. I only have one can of powder on the bench at a time. Same with ammo at the range. One type of ammo on the table at a time. I was playing around with two Arisakas one day at the range. One I had re-cut to 6.5x55. I was looking through the scope at the target and reached over for another round and put it in the magazine. I felt a light recoil and jacked it out. I had put a 6.5x50 cartridge in the 6.5x55 rifle. That was the longest , thinnest 6.5x50 case you ever saw. It formed perfectly to the other chamber. Be careful. This stuff can happen to you.

  8. #53
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    Quote Originally Posted by maxfaxdude View Post
    I'll probably catch hell for saying this. But this is why I NEVER shoot handloads or reloads!
    Factory loads are no guarantee

  9. #54
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    4198 is a long grain low density fast powder , i was loading my ackley swift , opened a fresh can of 4350 if that what you call a sealed can twenty years old , now this ruger likes 3800 fps , loaded to what the specks said on the ammo as i keep a record on the right stuff , first shot over the crony showed 4260 fps . blown primer , flattened hard to lift bolt , . Back home I pull the projectiles , loaded some 222 rems with the same value as 4320 , got the same velocity , so i pored the can into a 4320 can . if the weight and volume are the same and the velocity is the same the powder are likely the same

  10. #55
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    Look at the breech face of the barrel in an M96 and then look at the breech face in a Springfield 03. The M96 Mauser breech face is flat and perpendicular to the chamber opening, while the Springfield's is angled, like a cone. There is a considerable length of the 30-06's case rear hanging in open space when the cartridge is locked into the breech. Only the case's extraction groove is exposed in the Mauser breech, and only in the extractor notch. (Hatcher's book describes this in detail.)
    All of my Mausers type 98s have a case head protrusion (hanging in open space) of .110", All of my 03s have a case head protrusion of .090" above the bottom of the extractor groove. And then there is the cone face; that means the 03 has less 'hanging in open space' than the Mauser. And then there is clearance so I add .005" to the case head protrusion.

    F. Guffey

  11. #56
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    Checking neck tension is one of those quality control checks I alluded to. With a hand press, you can feel the force needed to seat the bullet. If I feel that the bullet went in with less resistance than the rest, it gets culled.
    And that is the reason I do not use the term neck tension, If I want to determine bullet hold I use pounds. I would use neck tensions if someone would tell me how many pounds there were in tensions.

    F. Guffey

  12. #57
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    Quote Originally Posted by fguffey View Post
    All of my Mausers type 98s have a case head protrusion (hanging in open space) of .110", All of my 03s have a case head protrusion of .090" above the bottom of the extractor groove. And then there is the cone face; that means the 03 has less 'hanging in open space' than the Mauser. And then there is clearance so I add .005" to the case head protrusion.

    F. Guffey
    Take a look at the M96's breech face. The M96 is not an M98. Reread my post #19.

  13. #58
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    "Take a look at the M96's breech face. The M96 is not an M98. Reread my post #19."

    I have no idea why you are so hung up on that. EVERYONE knows this for gawds sake.

  14. #59
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    Quote Originally Posted by copperlake View Post
    "Take a look at the M96's breech face. The M96 is not an M98. Reread my post #19."

    I have no idea why you are so hung up on that. EVERYONE knows this for gawds sake.
    The M96 does not have a conical depression at the breech face. The rear of the chambered cartridge is nowhere near as exposed as in the M98.

  15. #60
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    Take a look at the M96's breech face. The M96 is not an M98. Reread my post #19.
    All of my Mausers type 98s have a case head protrusion (hanging in open space) of .110", All of my 03s have a case head protrusion of .090" above the bottom of the extractor groove.
    "Take a look at the M96's breech face. The M96 is not an M98. Reread my post #19."

    I have no idea why you are so hung up on that. EVERYONE knows this for gawds sake.
    You know they have a hangy out thing? I do not care what it is I measure case head protrusion and I measure unsupported case head.

    F. Guffey

  16. #61
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    I am not aware of ANY Gunsmith who will anneal ANY receiver in order to D&T due to legal liability issues.
    I have seen some VERY hard actions, (including a Remington Rolling Block that I own. The tang blew out 5 hardened bits that did not even mar the surface!) that needed special bits to cut the surface of the receiver.
    Look at the way the side blew out, and I wonder if he had a bore obstruction, or possibly the wrong diameter bullet?
    Or, just possibly, he did not weight out his powder charges and instead relied on a powder thrower [some call it a measure], which can, and will, give you varying amounts of powder. He may also have missed his "measurement" mark...
    Badger Jack

    One OLD Vets experience and opinion...


  17. #62
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    Here are a couple of Carl's I intentionally exceeded their service duty. I tig welded them back together as how they sorta looked like they came undone. The upper action had four holes drilled and one could imagine that the let-go was from a crack that can be seen going through one hole. The lower has two holes and no crack through any. Get over that the drilling has anything to do with propagation even though one sees it going through a hole in the former. Just look at how it came undone. The right side of the receiver is only .950" thick. This is to accommodate the locking lug with the extractor over top of it in loading. Bolt closed to lock and now extractor is 'holding' cartridge head. Overpressure event seeks weakest point, that being, extractor/thin receiver wall. The port receiver wall is .155" and it lets go in that there is no caes head support. Tops fly too, but I do not think that has anything to do with holes.

    The strange grooves in the lower receiver were from me releasing the barrel.


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  18. #63
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    It was quite common to "Spot" anneal years ago. You took a pencil flame torch head and put a small cherry red spot where you were going to drill. I have never done it(That is why they made carbide), but there is nothing wrong with it. Welding, by Gunsmiths, has put more stories in books than spot annealing. It takes a tremendous amount of pressure to have a receiver come apart on the first shot. It is rare when an accident occurs and it is the receiver at fault. It does happen, but not often.

  19. #64
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    Case hardening does not add strength: https://en.wikipedia.org/wiki/Case-hardening

    Spot annealing does not make an action weaker.

    I have some 1894 Brazilian FN actions that laugh at carbide! They are impossible to face or drill without annealing. Mauser ones, not so much. One other note: welding bolt handles on older '93,4,5,6 bolts can be extremely frustrating because of the case.

  20. #65
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    It was quite common to "Spot" anneal years ago. You took a pencil flame torch head and put a small cherry red spot where you were going to drill.

    Or they used a carbon torch (stick) with a 12 volt battery and wires to complete the circuit.

    F. Guffey

  21. #66
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    copperlake- You are somewhat correct. Case hardening is mostly a wear factor in guns, however casehardening absolutely does add strength. If you were to put a bolt in a rifle that was just common, normalized 1020 (Average Mauser material) or even 1040, it would show a difference. After firing a few rounds, your brass case would start to get longer due to setback in the compressed material. I am not sure if spot annealing even works on case hardened parts, I have never had to do it. I have welded on cased receivers such as Mausers and Mosin Nagants. The area right next to the weld retained it's case. This is more of a heat treat business thing than a gunsmith problem. I have been in machining and gunsmithing over 40 years, and some of your most competent gunsmiths are usually lacking in knowledge of the differences in steel qualities. Heat treating is a business all it's own. I know enough to do what I have to, but am no heat treater.

  22. #67

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    Quote Originally Posted by maxfaxdude View Post
    I'll probably catch hell for saying this. But this is why I NEVER shoot handloads or reloads!
    If you can't be safe and sane, don't even think about handloading or reloading.

  23. #68

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    Quote Originally Posted by copperlake View Post
    Here are a couple of Carl's I intentionally exceeded their service duty. I tig welded them back together as how they sorta looked like they came undone. The upper action had four holes drilled and one could imagine that the let-go was from a crack that can be seen going through one hole. The lower has two holes and no crack through any. Get over that the drilling has anything to do with propagation even though one sees it going through a hole in the former. Just look at how it came undone. The right side of the receiver is only .950" thick. This is to accommodate the locking lug with the extractor over top of it in loading. Bolt closed to lock and now extractor is 'holding' cartridge head. Overpressure event seeks weakest point, that being, extractor/thin receiver wall. The port receiver wall is .155" and it lets go in that there is no caes head support. Tops fly too, but I do not think that has anything to do with holes.

    The strange grooves in the lower receiver were from me releasing the barrel.


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    Right on the money, Copperlake. The failure in the original post did not start at the hole. The crack you're seeing did not propagate FROM the hole - it ENDED there. (Don't forget, the classic fix for a crack was to drill a hole at the tip, which would often prevent the crack from spreading.) The pattern on the fracture surfaces, plus the layout of the flap and hinge structure off the right side of the receiver, shows that it started in the thin (right) side of the receiver wall. I started working on failure analysis investigations in '94, working with an incredibly talented engineer, and spent half that time looking at fracture surfaces under the microscope. The pattern on the fracture face tells a story as clear as a road map, in most cases; you just have to be skilled at that kind of map reading. Luckily, the people I've worked with over the years are that skilled.

  24. #69
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    cdxs, thanks for the comment. There is quite a difference between thinking about an outcome and actually creating an outcome. And then, with results in hand make a reasonable estimation of what happened. I have read the darndest theories about these sorts of things; just witness some of those on this very thread. When you actually do it intentionally there is this strange feeling that comes with that effort - that would be - you have an intimate look at something unusual.

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