I no longer have an FN action but as I remember the extractors had a Rockwell penetrator mark on top of the extractors.
This one has what appears to be the same mark adjacent to the dovetail that engages the groove in the bolt head.

Speculation is fun but without difinitive information we'll never really know. Some have raised the question of loads - on that note I picked up two .270WSM cases at the range yesterday both showed horrible pressure signs. I later (at home) measured the case mouths. Both mic'd .262"!!!!!

As much as we hate to admit it pilot error causes more problems than not.

quote:

Originally posted by T.Carr:
New Photos and more info from the gunsmith.

From looking at the bolt face it looks like the bolt has seen very little use. There's no brass marks from feeding anywhere. Even that sharp little corner left by opening the bolt face below the extractor slot should have piled up a pound or two from difficult feeding scrubbing that corner. Firing pin hole has a little burr that looks like the bolt is soft. Extractor collar is usually much softer than bolt body shows very little wear making me think this saw very limited use. Extractor slot when viewed from the root of the lug shows it was cut too deep. The bolt looks to me like it was rarely if ever used and maybe it's soft and was just barely pushed pase it's yield point with a "normal" reloaded 264 mag. When reading Ackley's books, he used a 270 short magnum for his blow up tests because it was hard on actions. I'd bet the 264 is right behind it.
gunmaker

quote:

Originally posted by Gunmaker:
...with a "normal" reloaded 264 mag. When reading Ackley's books, he used a 270 short magnum for his blow up tests because it was hard on actions. I'd bet the 264 is right behind it.

Mr. Ackley mentions 264Win failures on page 37 of Volume II, but he was talking about the Chambers being too thin on the Featherweight M70s.

Very interesting flicks which I've saved under "Cumulative Metal Fatigue". But, Gunmaker has made some very astute observations.

The original posting says this is a commercial FN so as I understand things it would not have been a war time production.

The pictures reminds me of the results we had when we tested varius actions for static presure strength in a hydraulic press
Stopping the minute we heard it crack.

It showed similar results as obtained with wery hard bolts and recievers.

Even light loads on this bolt would result in complete faliure.

The third lug would help wery little as the reciever generaly splits around the thumbcut.

quote:

Originally posted by DArcy_Echols_Co:
I have seen more heat treat issues with FN actions than any other comercial 98. I have even seen some in the white actions to be completely soft. .

Didn't I read on AR a year or two ago that FN sold actions which HAD to be hardned by the buyer. Maybe some didn't, and maybe some didn't do it properly.

quote:

Originally posted by Ricochet:
We don't know what this rifle's owner considers "normal reloads," do we?

Well and truly said. The use of the terms "Normal handloads" and "264 Win Mag" in the same sentence strike me as something of an oxymoron.

quote:

Originally posted by JAL:
Didn't I read on AR a year or two ago that FN sold actions which HAD to be hardned by the buyer. Maybe some didn't, and maybe some didn't do it properly.

Anything is possible but this would be news to me....I seriously doubt it.

Well in light of DArcy_ etc. experences, does this mean the FN Co. is at fault, or that aftermarketers get a perfectly good action and soften it or also overharden it?

quote:

Originally posted by JAL:

Didn't I read on AR a year or two ago that FN sold actions which HAD to be hardned by the buyer. Maybe some didn't, and maybe some didn't do it properly.

receivers, no bolt, and yes, sarco is still selling them.

jeffe

quote:

Originally posted by jeffeosso:


receivers, no bolt, and yes, sarco is still selling them.

jeffe

Jeffe, As I recall these are single shot receivers.....am I right here?

quote:

Jeffe, As I recall these are single shot receivers.....am I right here?

not sure if they're single shot, but they don't have the ejector slot cut or the hole drilled for the ejector box screw, and i'm pretty sure there is no third lug recess. isnt there a thread here in the last day or so about someone working with one of these? pretty sure...

quote:

Originally posted by Harry:
The original posting says this is a commercial FN so as I understand things it would not have been a war time production.

That's not necessarily so. Many wartime bolts were repurposed as sporter bolts. Or, bolts dating back to just before the war were utilised. The bugaboo here is that these altered bolts were simply heat treated without first annealing the previously hardened bolts. Thus the ass end was correct whilst the front ended up too hard.

In 1991, I had something very similar happen with the bolt face of a 7mmRemMag built on a 1945 Mexican Mauser, only the bolt face broke completely off. The large flange of the Mauser bolt shroud protected my right eye from the escaping gas and brass particles. The rest of my face was peppered pretty good, and my left eardrum was decimated by the concussion. The third lug held, but the action buckled enough to break the Fajen-Reinhart stock into 3 pieces.
The fracture ran from the split lug, through the firing pin hole, and extended to the opposite side, just below the other lug. Almost half of the bolt face was gone, including half of the split lug. The load was 65.0gr of IMR4350/140gr Partition, a load I'd been shooting in that rifle for over 20 years. I asked Jack Belk's opinion at the time, and he said it was probably poor heat treatment, common to many Mexican Mausers of that vintage.

Vapo,
if I recall correctly, there were some sold, without third lug cut (so a bolt couldn't go in it.. unless some grinds the third lug off), but most of them where solid wells for mags.


that all being said, this is a BOLT failure.. a stretchy action would have sagged, allowing the bolt to ride back.. think lug setback on speed.... and when you cammed the bolt open, the rear of the action would have cammed the bolt forward, back into battery, and allowed it to open...

so, the action softness has jack to do with this... but, of course, the lug contact could.


frankly, this looks like an annealed or unhardened bolt to me

jeffe

Jeffe,
An annealed or unhardened bolt would have deformed or yielded same as a soft or annealed receiver. This is a brittle fracture - too hard.

ireload,
i beg to differ, though this may be quibbling.. a too soft receiver would not result in a cracked bolt, such as this.

this could be the result of a dead soft bolt, as the cracks are running in two failure modes.. the left side obviously failed first, and a piece cleved... sure enough... then the right lug let go, probably do to the left lug holding all the "weight"...

i sure would like a 100x picture of the metal surface under both cracks... would tell us in a bout 90 seconds if the metal was too hard ... and would have additional surface cracks, or too soft, and yielded..


there should be visual, though requiring strong magnification, clues to show us sheer or cleve... ... like the surface of a too had drill rod that snapped, or a piece of too soft metal that gave way... totally different faults

jeffe

I have a copy of issue 1 of the 2004 African Hunter that has a technical 5 page article about the strength of the k98 action. It is by Chris Bekker. I think it might shed some light on the subject. Maybe Don Heath would reprint it in the AR or send it to those who like something technical to read. I would even make a copy and fax or mail it to someone.

quote:

Originally posted by jeffeosso:
ireload,
i beg to differ, though this may be quibbling.. a too soft receiver would not result in a cracked bolt, such as this.

this could be the result of a dead soft bolt, as the cracks are running in two failure modes.. the left side obviously failed first, and a piece cleved... sure enough... then the right lug let go, probably do to the left lug holding all the "weight"...

i sure would like a 100x picture of the metal surface under both cracks... would tell us in a bout 90 seconds if the metal was too hard ... and would have additional surface cracks, or too soft, and yielded..


there should be visual, though requiring strong magnification, clues to show us sheer or cleve... ... like the surface of a too had drill rod that snapped, or a piece of too soft metal that gave way... totally different faults

jeffe

Jeffe,
Dead soft steel does not crack like this. It will yield before it fractures. This bolt clearly did not yield before it cracked.

quote:

Originally posted by army aviator:
I have a copy of issue 1 of the 2004 African Hunter that has a technical 5 page article about the strength of the k98 action. It is by Chris Bekker. I think it might shed some light on the subject. Maybe Don Heath would reprint it in the AR or send it to those who like something technical to read. I would even make a copy and fax or mail it to someone.

Hello Army Aviator,
I would appreciate a copy of the Mauser strength article. I will PM you with my email address.

ireload,
i can't see that from the picture, but I am certain some folks can. i would like to see a blown up high mag pic of it. can't agree or disagree with you, so until I heard of someone running a hardness file over it, I wouldn't venture a guess.

jeffe

This might be the article. If not I have no idea if anything in this article by Cris Beckker is applicable to this conversation.

Ok, I tryed to make it a link but couldn't so here's the web address www.deerstalker.com/mauser_action.htm

Might be intesting reading though.Since I have NO expertise in such gunsmithing matters I sit on the side line and read and hopefuly learn.

Allen

Huh! It worked, I'll be darned.

The article mentions the CZ 550 as being "investment cast". Isn't that a blatant mistake?

quote:

Originally posted by duikerman:
[QUOTE]Originally posted by DArcy_Echols_Co:
The bolt face failed in the same manner. Later inspection found the bolt body over all was way to hard when tested on the "C" scale.

That is why I will never have a Mauser re hardened If it was good enough for the first hundered years who am I to improve on the casehardening

My origional thought about the bolt being soft was from looking at the pin hole. After looking at the face some more, maybe they milled the bolt face after hardening, then turned it into a magnum. The color is a little cleaner on the face compared to the rim and split-nose. They could have used too much heat before quenching too. Some 03's had that problem.

quote:

Originally posted by ireload2:

quote:

Originally posted by army aviator:
I have a copy of issue 1 of the 2004 African Hunter that has a technical 5 page article about the strength of the k98 action. It is by Chris Bekker. I think it might shed some light on the subject. Maybe Don Heath would reprint it in the AR or send it to those who like something technical to read. I would even make a copy and fax or mail it to someone.

Hello Army Aviator,
I would appreciate a copy of the Mauser strength article. I will PM you with my email address.

I was starting to get this article ready to E-mail you but was having some trouble making a clear copy. I see you can just click on in from AllenBosely's post.

Side-Bar. How strong can an action be? I remember reading in an NRA magazine around 9-11 plus or minus a couple of years about a guy who had a Japanese Arisaka rifle that he took to a gunsmith and complained that it kicked to much. He wanted a recoil pad or something. It turns out he was shooting the wrong size bullets through the rifle. It was sent to the NRA where their lab test determined it was withstanding over 200,000PSI. At least that the way I remember the article.

quote:

Originally posted by army aviator:
Side-Bar. How strong can an action be? I remember reading in an NRA magazine around 9-11 plus or minus a couple of years about a guy who had a Japanese Arisaka rifle that he took to a gunsmith and complained that it kicked to much. He wanted a recoil pad or something. It turns out he was shooting the wrong size bullets through the rifle. It was sent to the NRA where their lab test determined it was withstanding over 200,000PSI. At least that the way I remember the article.

Something like a 8mm in a 6.5mm. The fired bullet was WAY long & skinny swaged rite down though

quote:

Originally posted by army aviator:
Side-Bar. How strong can an action be? I remember reading in an NRA magazine around 9-11 plus or minus a couple of years about a guy who had a Japanese Arisaka rifle that he took to a gunsmith and complained that it kicked to much. He wanted a recoil pad or something. It turns out he was shooting the wrong size bullets through the rifle. It was sent to the NRA where their lab test determined it was withstanding over 200,000PSI. At least that the way I remember the article.

PO Ackley wrote of blow up tests (which may not be valid comparisons) that he conducted. He found the Type 38 Arisaka was the strongest.

I will add my 2 cents about the gas handling qualities of a 98 Mauser. I have seen a guy that was hit in the face by gas out of a 98 design. The rifle in question was one of the Herter's Mausers that had been in a fire. He had reblued it and restocked it. Caliber was .243. It let go on the 3rd shot. He had 20 or 30 small leaks on his face though none got his eyes. It looked terribly unpleasant to say the least. He was not able to unlock the bolt but it did blow the stock open and cracked it down into the pistol grip.

ireload,
parker found the last ditch arisaka to be the most durable, and seemed to get annoyed that he couldn't blow it up.. because is STRETCHED soo much....

wasn't the strongest, it was the softest, but took the most damage

the guy with the hard kicking gun was shooting machinegun ammo in the bolt gun

jeffe

jeffe

As Savage99 said above I also have some photos of a Swede bolt with lugs sheared off. I lost the story with a hard drive crash, just have the photos.

Swede lug failure

quote:

Originally posted by jeffeosso:
ireload,
parker found the last ditch arisaka to be the most durable, and seemed to get annoyed that he couldn't blow it up.. because is STRETCHED soo much....

wasn't the strongest, it was the softest, but took the most damage

the guy with the hard kicking gun was shooting machinegun ammo in the bolt gun

jeffe

jeffe

Jeffe,
Page 6 of my "Pocket Manual for Shooters and Reloaders" says

"The 6.5 action is especially stong, and in blow up tests has proven to be the strongest military action tested"

The hard kicking Arisaka was a 6.6 rechambered to a 30/06. The NRA tested it but there was nothing like 200,000 psi involved. As Ackley pointed out the bullet has only to move a short distance before it is swaged down to 6.5.
Good Luck!

ireload,
get ackley's "handbook for shooters and reloaders" vol 1 and 2 that has the entire story on what he did to test it and how he tried to blow it up. it's quite an interesting read, and spreads over several pages. i would imagine the pocket manual only hits the high points.

jeffe

quote:

Originally posted by Badboyz:
The article mentions the CZ 550 as being "investment cast". Isn't that a blatant mistake?

Good old Brno/CZ's huh?
Don't know about the 550 in particular, but I have in front of me an article where a gunwriter did a tour of the CZ factory.
A colour photo shows "Castings of bolt bodies ready for machining".
Another, "Cast receivers in a partially machined state."
And from the article, "Many of the firearm parts are cast using the lost wax method. I have seen this process used in a Ruger plant in the USA. About 30-40% of rifle parts are built in this way."

Guns & Game, Oct-Dec. 2006. A Visit TO CZ by Briel Jackson.

Seeing how this subject has been partially hi-jacked, I'd like to relate a situation I found myself in while attending the Colorado School of Trades. A friend of mine and an instructor there, had a 7.7 Arisaka that he wanted to destroy so, he started out with 10% overloads (according to the the manuals) and loaded an 8 M/M projectile in it. It digested them like there was no tomorrow with no ill affects. He then went to 20% overloads and 8 M/M bullets and promptly locked the bolt shut. We repaired to the school and removed the barrel and the semi melted case from the chamber and bolt face. Nothing else seemed to be amiss but, being somewhat careful, decided to take it apart quickly. The rifle was reassembled and a Norma case full of Bullseye and an 8 M/M bullet was chambered. Upon detonation, the safety disappeared as did the extractor and the top of the front receiver ring. The barrel wound up about twenty feet in front of the action, apprently in good shape with the nose of the bullet slightly protruding from the muzzle. I wish we had taken pictures of that. It certainly goes along with Ackley's opinion that the Arisaka was the stongest (if not the ugliest) of all the WWII military actions.

First I want to say that I own about a dozen Mauser rifles of assorted manufacture and am a big fan. I also want to say that even the "venerated" Mauser 98 is a mechanical device and like any mechanical device can fail.
I want to follow up Masterifleman with my story. Actually, it was a co-worker who bought a $49.99 Turk Mauser from Big 5 sporting goods. This guy had no business AT ALL reloading, but did anyway. He scrounged any brass at the range to convert to 8x57, and i personally think thats what led to the rifle's demise. Anyway, I was at the local gunsmith shop when he came in with it. He had blown the stock to bits, looked like a grenade had exploded in the magazine, and the bolt lugs were both sheared similar to those shown here. The crazy thing is he wanted the 'smith to FIX it so he could shoot it some more. He said he loaded....wait for it.....Normal Loads and had no idea what happened. It was also the second gun he had "Detenated" in 3 years, the first being a Star PD 45acp. He is no longer with us so we wont know what happened, but I suspect he was loading WAAYY to hot and probably trimmed a case too short.
Anyway, I am glad that no one hurt and it gives us something to discuss here at AR.
Eterry

More info from the gunsmith:
************************************************************************************


It has been shot enough to wear out the original barrel and was rebarreled 5-10 years ago and shot quite a lit more since then.

When I said the reloads were “normal†I meant that that the bolt handle lifts easily and the brass shows no unusual pressure signs.

Further conversation with the owner:

·Owner had been shooting the rifle for years with no problems.

·At the range, preparing for deer season, first (?) shot caused a head separation. Session terminated. Fragment extracted with brass brush in normal bore cleaning session.

·Back at the range, the first shot caused another head separation. Removal of fragment as before.

·Back to the range for session #3 with same reloads but prepared in new, unfired brass. First shot caused incipient head separation. Gun brought to gunsmith for examination.


Here is a picture of the left lug after the upper fragment fell off by itself even with gentle handling.



Here is a picture of the “contact†side of the safety lug.



Here is a picture of the “contact†side of the root of the bolt handle.




Here is a picture of the bolt being tested for hardness with a calibrated Rockwell C machine. Note the remaining portion of the right lug tested at 64.5. [We also tested the right lug of another FN commercial bolt at 64.0]


The bolt head tested 62 about ¾ inch behind the bolt face and between the lugs.

The left lug tested 68.5. Wow! That’s HARD.

The safety lug tested 61.

The base of the bolt handle tested 58.5