Sheared Bolt Lugs - Swedish Mauser

[Dutchman]

m/1896 Swedish Mauser in Australia. Details of failure unknown to me.

Those of you with metallurgical experience are most welcome to comment... though I know its hard to make a definitive statement based on such limited information.

As with the 1893 Mauser photos I post these photos to illuminate the reality that seemingly strong and sound rifles suffer catastrophic failures and sometimes people are killed as a result. What exactly caused this incident, had it killed the shooter, would be immaterial to his widow and children. Dead is dead.

http://images108.fotki.com/v611/photos/2/28344/377112/brokelugs1-vi.jpg

http://images38.fotki.com/v1274/photos/2/28344/377112/brokelugs2-vi.jpg

http://images39.fotki.com/v1285/photos/2/28344/377112/brokelugs3-vi.jpg

http://images36.fotki.com/v1296/photos/2/28344/377112/brokelugs4-vi.jpg

pietro - resist the urge to hijack a thread that I start so you can make some idiotic statement.
What you did was rude and I don't like rude.

Dutch
Contributor to [only] two books on Mauser rifles:
"Crown Jewels: The Mauser in Sweden" by Jones
"Mauser Military Rifles of the World" 4th edition by Robt. Ball

[TRX]

No sign of the "seashell" marks indicating fatigue cracking. The granularity of the broken area suggests that the bolt is a casting. Hmm.
I'm going to forward the link to a couple of guys who have some expertise in failure analysis and see if they'll venture an opinion.

I can visualize all the guys with the third-locking-lug actions nodding and snapping their suspenders now...

[Bret4207]

Yup, but the bolt handle is intact which means that sucker didn't come flying out into the guys forehead. I'd also venture a guess that primer pocket is a bit larger than normal. Obstructed barrel? Over load? There are pics here of Marlins and Remingtons and Winchesters all blown to heck too.

[Johnch]

Saw a bolt almost exactly like that a few years back at the gun club

Story was the fool was shooting Hornady Light Mag ammo as his standard load

Tryed to work up his own at those velositys

First 10 or so no problem
#11 the lugs sheared off

Probely filled his shorts

John

[Dutchman]

The granularity of the broken area suggests that the bolt is a casting.


No Mauser military bolt made any where at any time was a casting. These are forged bolts.

The fellow who supplied the photos was a former Australian army small arms amorer. I asked him twice for more info but he just didn't have any further information.

Dutch

[Cap'n Morgan]

Yuuk! Brings back memories...

http://castboolits.gunloads.com/showthread.php?t=31989

At least the lugs didn't shear in my case.

I wonder if it is brass from the case you can see at the firing pin hole in one of the pictures, or if the bolt face/hole had been tampered with (brazing).
I read somewhere that the hardening process of the 96 Mauser bolt and reciever was quite an intricate process. If some amature decided to 'improve' the bolt by hardening, it would explain the 'brittle' apperance of the fracture surface.

[pietro]

[Beware of anyone who tells you how strong these small ring Mausers are.]

The problem is, most wouldn't know a real Small Ring Mauser (which the M-96 most decidedly is not) if it bit them in the butt.

Just because a Mauser action has a front receiver ring the same diameter as the left receiver sidewall, doesn't make it a "Small Ring Mauser".

The term "Small Ring Mauser" refers specifically to cock-on-opening Mauser 98's of that description - which has all the safety features of the Large Ring Mauser 98 - and specifically NOT to any of the cock-on-closing Mauser Model 93's, 94's, 95's, & 96's - which lack those features.

[Dutchman]

The problem is, most wouldn't know a real Small Ring Mauser (which the M-96 most decidedly is not) if it bit them in the butt.

Just because a Mauser action has a front receiver ring the same diameter as the left receiver sidewall, doesn't make it a "Small Ring Mauser".

The term "Small Ring Mauser" refers specifically to cock-on-opening Mauser 98's of that description - which has all the safety features of the Large Ring Mauser 98 - and specifically NOT to any of the cock-on-closing Mauser Model 93's, 94's, 95's, & 96's - which lack those features.

http://www.mausercentral.com/rings.htm

http://www.brownells.com/aspx/NS/GunTech/NewsletterArchive.aspx?p=0&t=1&i=43
"The next size larger is the so-called “intermediate” size action of which there are several examples. The most common of these are the 1893-1895 Spanish Mausers and the 1894-1896 Swedish Mausers. These are the pre-98- style, small ring Mausers that have the long, non-rotating Mauser extractor, familiar ejector box on the left side (rear) of the receiver and the enclosed staggered-round magazine."

http://www.rawles.to/Mauser_FAQ.html

http://www.midwayusa.com/ebrowse.exe/browse?TabID=10&Categoryid=11709&categorystring=657***8705***

http://castboolits.gunloads.com/showthread.php?t=26210

Twice in one night...

Dutch

[Buckshot]

[Beware of anyone who tells you how strong these small ring Mausers are.]

The problem is, most wouldn't know a real Small Ring Mauser (which the M-96 most decidedly is not) if it bit them in the butt.

Just because a Mauser action has a front receiver ring the same diameter as the left receiver sidewall, doesn't make it a "Small Ring Mauser".

The term "Small Ring Mauser" refers specifically to cock-on-opening Mauser 98's of that description - which has all the safety features of the Large Ring Mauser 98 - and specifically NOT to any of the cock-on-closing Mauser Model 93's, 94's, 95's, & 96's - which lack those features.

Hmmmm. All these years it seemed (to me at least) almost universaly common to gather all the PRE1898 design Mausers (1889, 1891, 93, 94, 95, & 96) into the genre of "Small Ring" Mausers and their licensee's (FN, Spanish Gov't, and the Swedes). All the 1898 and beyond with the 1898 improvements falling into the "Large Ring" family.

Just as there were differences in the various 'small rings' so too there were differences in the so called M98 Large rings. Standard and short length actions, Turk large rings accepting small ring threaded barrels, G33/40 Mountain, etc & etc.

If the early cock on closing M89 to M96 designs aren't small rings, what are we to call them?

...............Buckshot

[Bret4207]

"The term "Small Ring Mauser" refers specifically to cock-on-opening Mauser 98's of that description - which has all the safety features of the Large Ring Mauser 98 - and specifically NOT to any of the cock-on-closing Mauser Model 93's, 94's, 95's, & 96's - which lack those features. "

Huh. Thats the first time I've ever heard the term "small ring" assigned to any '98 design. My library goes back to the 19th century and none of those resources refer to a '98 design as a small ring. Short, intermediate, magnum, yes, but not small ring. Luwig Olsons Mauser book makes no mention of this either. Where did you get this definition Pietro?

[TRX]

The guy I really wanted to have a look is a failure analysis expert. However, he couldn't venture much of an opinion since the pictures were deleted.

Another, who managed to take a look before the pictures went away, said the large grain size was sometimes seen after a bad heat treat.

[C A Plater]

I thought the term small ring and large ring when applied to Mauser rifles meant the barrel shank of the small ring was .980" and large has a 1.10" shank both threaded 12 TPI.

[mike in co]

i am by no means a mauser expert, but there has been a pretty clear definition in my mind of small ring and large ring mausers.....alot of it provided by my fellow cast boolit members.


so sir, you are going to have to provide some documentation on your opinion....cause it is just your opinion till proven to the rest of us.

having said that , most of us are willing to learn.

mike in co

[pietro]

Bret - I guess I have several replies, some stemming from over 45 years experience with these rifles, and others from my own library - and yet still more provided by a few of the above critics who either excerpted what suited them from a source, or didn't bother to read the source they hyperlinked.

Mike in co - I have stated a fact, and not my opinion - as attested to over many years by real (not internet) experts, like Frank deHaas for one (see: BOLT ACTION RIFLES, Military Rifles & Actions, Mauser Model 98, pp 103/104).

Dutchman: Why not paste the entire Brownell's section, like where the Small Ring Model 98 in described as one of the four Mauser variations, instead of just what fit your agenda ?

Also, Dutchman, in your posted hyperlink to the MidwayUSA tech section, the Model 98 is listed under Small Ring Mauser's, just waiting to be read by any who cared to:

"Small Ring Mauser - Mauser 34, 38, 91, 93, 94, 95, 96, 98 (Small Ring), 99 & All Other Military Model Numbers (except Large Ring Mauser 98)"


Buckshot - [What are we to call them ?] - Good question.
IMO (and this IS an opinion of mine), pre-98 Mausers are "Mausers with small rings", but M-98 Mausers with small rings are "Small Ring Mausers", decidedly different.
What's not opinion, but fact - is that the defining feature that separates them is that the "pre-98's" are all "cock-on-closing" (unless aftermarket converted), while M-98's are all "cock on opening".

.

[runfiverun]

i always based it on the distance from the 2 screws holding the action into the stock.

[mike in co]

[Beware of anyone who tells you how strong these small ring Mausers are.]

The problem is, most wouldn't know a real Small Ring Mauser (which the M-96 most decidedly is not) if it bit them in the butt.

Just because a Mauser action has a front receiver ring the same diameter as the left receiver sidewall, doesn't make it a "Small Ring Mauser".

The term "Small Ring Mauser" refers specifically to cock-on-opening Mauser 98's of that description - which has all the safety features of the Large Ring Mauser 98 - and specifically NOT to any of the cock-on-closing Mauser Model 93's, 94's, 95's, & 96's - which lack those features.


sir p, you leave most of us confused...in one mouthful you calim 96's are not small ring and then post references which say 96's are small ring.



so quit posting YOUR opinion, and POST some facts!...not a reference to a book, but the rext from the book ....

this single reference...with no supporting text, appears in error to begin with as it is a 98 reference......not a small ring refference.....so post the text.

to the members here it is your opinion untill you post known supporting documentation...which you have not done....again post supporting text.

riverrun.....we are talking "ring" not length......bolt holes would be action length...an entire nother subject.

[MtGun44]

Anybody have the pix? I do failure analysis as part of my job in
the aerospace industry for over 30 yrs. I'd like to see the fracture
surface at least.

In my experience, small ring is normally the pre-98 Mausers, but there
are some 98's that have smaller rings, but this is not what is typically
meant when the term is thrown out.

I have a very nice 95 DWM Chilean Mauser in 7x57, but I definitely keep
the loads to the levels in the normal manuals - 45K psi. No matter how
nice the workmanship (it is amazing) the knowledge and science of
steel manufacturing, alloying and heat treating were relatively crude in
1895. "Best steel" in those days would be pretty average by today's
standards.

Bill

[Buckshot]

...............To me, and maybe common concensus is that the term "Small Ring Mauser" does mean any of the Mauser, Loewe, FN, Spanish, and Swede manufactured bolt actions without the 1898's embellishments. Having had a keen interest in surplus military rifles, and having had an 01 FFL since 1980, it's simply been a given that when the average Tom, Dick, and Harry says Small ring, they know he means that series of Mauser designs pre-dating the 1898.

It must be fairly common because in most all the adds for, and catalogs from the various importers after the 1986 importation relaxation, has simply refered to these types as Small Rings. I've never researched for, nor authored a book on Mauser rifles so I am no expert on their minutiae. I have read a lot about them though, and again it appears to me that common and understood (recognized) nomenclature is Small ring and Large Ring.

Actually the Small ring family is fairly simple as their variations are pretty much cosmetic details especially among those after the '93 Spanish. So far as I know the round bolt Small Ring bolt will fit and work in any Small Ring action. The chinned Small Ring bolt being the exception and a Dremel will remedy THAT simple problem :-)

It appears to me that all the real exceptions and mystery is involved with the 1898 design. ALL Small Rings have the same ring OD. They are all of the same length, and share a common barrel thread OD. The exceptions ly with the so called Large Ring versions. They can have BOTH ring OD's and still be in the Large Ring family because they also retain the 1898's other identifying features, such as the 3rd lug, internal ring collar, improved bolt shroud and takedown feature, etc.

Also their overall lengths can vary. The ring lengths can vary, plus you have the Turkish made K. Kale's that are true 1898's except they take the (dare I say it) Small Ring barrel shank. To my way of thinking we could have 3 groups without too much confusion. You'd have the Small Rings. Large Rings (which are well known as the M98's), and then possibly Small Ring 98's?

.................Buckshot

[twotrees]

I run the Fracture and Fatigue Lab at Ga Tech and we do a LOT of testing on materials. ( Now Called the Mechanical Properties Research Lab)

The Picture I saw was large grained and no to little ductal "lips" any where.

If I had to guess, from what I saw it was catastrophic Fast Fracture.

I would like to have seen the receiver too, as that could help in saying something about what caused it to fail in that manor.

The 93 Mauser was the first use of modern metallurgy from the design phase forward. They picked the steel and heat treats Before they made up the gun instead of making one then trying to figure out what needed changed after trials.

When (in another life) I built rifles on Mauser actions Bill Rodgers (Owner of Springfield Sporters, Importer of 90% surplus Mausers to the US) cautioned me only about making sure that the barrel shank and threads were a tight crush fit to the receiver. I custom built the stocks to fit the 16.5"-18" barreled rifles. They made nice light walking woods Varmint rifles.

I have cut down the length of both bolts and receivers on "Small Ring Mausers" and had them rewelded , with nickel wire and made pistol cartage rounds.

From the cutting phase and the welding phase the metal they used was very predictable and uniform.

The Failure seemed to be from a gross overload more than a metal problem.

Just My Opinion (and we all know all of us have one of those, like something else we all have)

[MtGun44]

Twotrees,

Thanks for the info. So much in failure is dependent on a really good look at
the broken pieces. If there is no apparent pre-existing fatigue crack ( and in
your job you have seen plenty of those, I'm sure) then it does sound like a sudden
failure. I agree totally that I'd love to see the receiver and barrel.

It has always impressed me how rarely we see catastrophic destruction of
firearms, even though I have personally witnessed three strong rifles in .223
blown up by seriously overlength brass. No injuries whatsoever and one of
the three was fairly easily repaired (new bolt/carrier assy) and was fully
functional. Two ARs and Mini14. Pressures must have been at least 90K and
likely well over that, given that ~75K is considered a normal proof load.

In any case, if anybody can get more pix a few of us out here who do this sort
of reading of bones and chicken entrails professionally and are firearms hobbyists
would like to learn more about what happens when things go very wrong.

And +1 for what Buckshot said. . . .

Bill

[Ricochet]

Isn't it amazing how often we see pictures of totally destroyed firearms and read that the shooter suffered relatively minor injuries or none? Bet it's a terrifying experience to hold one that kabooms, though! I hope to never find out.

[jonk]

Just to consider the small ring/large ring debate:

When I hear small ring/large ring, to ME it means a 98, period. Either it is large ring (98, 98k, etc.) or small ring (33/40, Kar98A, etc) or perhaps a hybrid like the turk guns- large ring, small shank for instance.

Pre-98s may coincidentally have a small ring diameter; however I usually hear them referred to as such, a "pre 98".

I have no reason for this opinion, it was just my understanding.

[Dutchman]

Isn't it amazing how often we see pictures of totally destroyed firearms and read that the shooter suffered relatively minor injuries or none? Bet it's a terrifying experience to hold one that kabooms, though! I hope to never find out.

Scroll down the page to this:

The photos are courtesy of the Swedish state criminal forensic laboratory. The shooter was killed when the breechblock split in two and half lodged in his skull behind his right eye.

http://dutchman.rebooty.com/RBfailure.html

I don't particularly like preaching but I like less hearing about fellow shooters being killed.

Dutch

[Ricochet]

That is awful!

You sure can get killed when a gun kabooms, but still, it's amazing how many times it's a much better outcome than you might expect.

[Larry Gibson]

I find it rather hard to believe that the bolt pictured is forged. Problem is I've never heard of a cast bolt for Mausers. Given the still excellent appearing condition of the action and the minor damage to the case I'd have to say that the load was not really over pressure. Not the primer pocket is not "blown", only to top of the primer is missing along with the anvil. I have also seen several cracked Mauser bolts from over loads and none had the granular structure exhibited in this case. Interesting to say the least.

Larry Gibson

[Dutchman]

I heard of another bolt lug failure in Sweden with a m/38 rifle. Was with standard ordinary m/41 military ammo but the lugs sheared and killed the young soldier. This causes the Swedish military to withdraw all Mausers from service. This wasn't more than 7 yrs ago as I recall but my memory sucks canal water. The person who told me was a former sergent in the Swedish army and vice-president of the largest gun collector's org in Sweden.

The only current use of Mausers in Sweden is with the Liv Guard (KI), the 1st kavalry who guard the Swedish palace in Stockholm. They have a daily ritual of the changing of the guard on horseback. They all carry loaded & locked m/94-14 carbines. They are not purely ceremonial.

Dutch

[skeet1]

Large ring, small ring, who cares what you think Pietro. I thought this thread was a discussion of the sheared bot lugs on the model 96 Swed. I would be much more interested in a continuance of the original discussion than what you think is large or small.

[stocker]

Interesting comments on small ring definition. I suggest Pietro may have something. All Mausers prior to the 98 (ie: the 93's, 95's, 96's) had similar sized receiver rings, front and rear so there was no necessity to have two terms (large and small ring). It wasn't until the 98's came along with different sizes that there was any need to discern between the two sizes. So on a practical sense the early models may have small rings but there is no need to identify them as such thus the term does properly apply but does when discussing 98's only. And if you are wondering, prior to this discussion, I would have thought the same as the rest of you as the early ones are small ringed but the description is moot in their case. I think score goes to Pietro in this case and we are all enlightened a bit. More a case of proper form of use of the term as compared to the obvious dimensional characteristics.

[405]

Yikes! While that does not look like the huge pressure of whatever caused the 93 failure it still looks like too much. And yes, agree with those who see the granular break seams on the lugs/bolt. Something is wacky. Crystal structure that coarse is not normal for properly heat treated/alloyed steels. Comparing that failure to that of the 93 provides some clues or at least something suggestive of differences in steel types or treatments.

[skeet1]

Dutchman,
It looks as though there is little or no damage to the receiver and extreme damage to the bolt. To me if this damage was caused by pressure or some other cartridge problem I would think there would be at least a little more damage to the receiver. My guess would be a bad bolt. I know the 96's are some of the best pre 98's but even moderns arms are not immune to bad materials and manufactrue recalls.

Skeet1

[Ricochet]

Something I've long wondered about is why the heat treating problems of the low numbered Springfields were only reported with those rifles. Surely the makers of Mausers, Lee-Enfields and such employed similar methods and materials.

[Bret4207]

Bret - I guess I have several replies, some stemming from over 45 years experience with these rifles, and others from my own library - and yet still more provided by a few of the above critics who either excerpted what suited them from a source, or didn't bother to read the source they hyperlinked.

Mike in co - I have stated a fact, and not my opinion - as attested to over many years by real (not internet) experts, like Frank deHaas for one (see: BOLT ACTION RIFLES, Military Rifles & Actions, Mauser Model 98, pp 103/104).

Dutchman: Why not paste the entire Brownell's section, like where the Small Ring Model 98 in described as one of the four Mauser variations, instead of just what fit your agenda ?

Also, Dutchman, in your posted hyperlink to the MidwayUSA tech section, the Model 98 is listed under Small Ring Mauser's, just waiting to be read by any who cared to:

"Small Ring Mauser - Mauser 34, 38, 91, 93, 94, 95, 96, 98 (Small Ring), 99 & All Other Military Model Numbers (except Large Ring Mauser 98)"


Buckshot - [What are we to call them ?] - Good question.
IMO (and this IS an opinion of mine), pre-98 Mausers are "Mausers with small rings", but M-98 Mausers with small rings are "Small Ring Mausers", decidedly different.
What's not opinion, but fact - is that the defining feature that separates them is that the "pre-98's" are all "cock-on-closing" (unless aftermarket converted), while M-98's are all "cock on opening".

.

Darn it! My copy of De Hasses book is buried in the barn. Well, all I can say is that the term isn't in common use. In your opening post you stated the following-"The problem is, most wouldn't know a real Small Ring Mauser (which the M-96 most decidedly is not) if it bit them in the butt." And-
The term "Small Ring Mauser" refers specifically to cock-on-opening Mauser 98's of that description - which has all the safety features of the Large Ring Mauser 98 - and specifically NOT to any of the cock-on-closing Mauser Model 93's, 94's, 95's, & 96's - which lack those features." But you also reference the Midway site which says the 93's, 95's, 96's ,etc ARE small rings. So you can see where I might be confused.

For now I'll stick with referring to MOST COO designs as small rings, with exceptions. No need to get hot under the collar about it. We've had horrible wars over terms like leade and throat and seat in the past. No sense going to battle over it.

[MtGun44]

Looks like a straight overload failure, now that the pix are back.
Tracking the 45 deg line as 'tensile' failures essentially always shift to
shear failures, leaving a 45 or nearly that angle failure surface.

No signs of a fatigue crack having existed prior to failure, just one
continuous and consistently textured failure surface.

Since the case is essentially intact, yet the primer is missing, I wonder if
it was a primer failure leading to very high gas pressure across the face
of the bolt. It would appear in this case that either gas venting was better
or the receiver ring was stronger - leaving the bolt to fail in the lugs due to
pure thrust load exceeding the strength of the steel, yet leaving the receiver
fully intact.

It would appear that there is inadequate ductility in the bolt, either poor
choice of alloy, heat treating too much for hardness at the expense of
ductility - or - the old question of the quality (and perhaps consistency!)
of steels in the early part of the last century or even late in the previous
century. Alloy mixing and heat treat were much less well understood in
those days.

If I were the engineer on this design, I would want considerable ductile
setback of the lugs prior to shearing, not this sort of failure.

Very impressive if no injury resulted.

Thanks for post the pix back to the thread.

I have a set of pix of a modern Sako action that failed in a totally
brittle way - split in half lengthwise due to (it appears) a barrel failure.
The extremely small amount of metal holding the receiver ring and rear
action ring together is seen in the broken halves, along with the totally brittle
behaviour. That one shows signs of an improperly hammer forged barrel
with deep internal fatigue cracks letting the barrel split into three nearly
equal pieces lengthwise. The case was petaled out in almost exactly
120 deg strips with an intact head. The pix seemed to show very brittle
action metal.

Again, (as Ricochet pointed out) it is amazing there was reported to be
no serious injury.

Bill

[math]

Yes that happends now and then and often you can see that there are rust under the lugs and a small new brake. It was more common when people used to use the powder from blanks just pulling the wooden bullet and replacing it whit a match bullet Not a recomended praktice!

Math

[M98]

small ring is small ring...it dont matter what model it is...there are small ring m98s....a large ring is a large ring....action is an action...no mater what it is...here is one example...the turks that are out there...some of them are a large action with a small ring long shank barrel...