Technically speaking, shear strength is a material property. I assume you are referring to the force needed to shear off one of the lugs (?). Whatever.

It was an intrersting article but, again, where is the evidence of failing Mod. 98 actions?

Cool guy,



For starters, the top (left hand) lug has got this cut running 'bout right down the middle in the axial direction. This reduces the shear strength of that lug by about 25%.



ASS_CLOWN

.

.

Alf,

I have absolute faith in the math, that when properly applied, it is nowhere near BS. Having said that I otherwise agree with your comments 200%. Having an established design, said Mauser dual opposed front lugs, and now coming along with an "analysis" which says it isn't strong enough for the task it has been doing quite well for over 100 years, tells me only one of two things.

1.) The guy performing this mathematical analysis is clueless as to what he doing.

2.) The guy performing this mathematical analysis is a lying sack, and is trying to sell something else.

I suppose there is an off chance the situation could be a combination of the two. Unfortunately, I find FAR TOO MUCH of item #1 in my day to day work. It seems to be especially true of the younger Americans and certain Europeans.

I have not read this magazine article, so I cannot be certain that it is actually saying the Mauser is too weak. I can only go off of the hearsay evidence posted here at AR that makes this claim about the magazine article. So my previous statements are being made in a general sense and are not necessarily directed to the aforementioned magazine article.

ASS_CLOWN

Lighten up Alf.

One should not throw stones, even ME!

Dentists are now promoting some treatment for some new, mysterious mouth bacteris, doctors (AMA) are anti-gun and aligning themselves with the latest national emergency (obesity, Ha!), vets are always preaching panic over some new fear (West Nile, heartworm, etc.), etc., etc.

Always good, I figure, to be skeptical of intentions and watchful for the money trail.

Alf,



IF you had taken the time to READ my entire last post, you would have noticed the DISCLAIMER at the end! I'll post it here again for your convenience.

Quote:

---

I have not read this magazine article, so I cannot be certain that it is actually saying the Mauser is too weak. I can only go off of the hearsay evidence posted here at AR that makes this claim about the magazine article. So my previous statements are being made in a general sense and are not necessarily directed to the aforementioned magazine article.

---

It is ASS to, not ARSE, you know as in "jackass".



If he stated that a 458 Lott, loaded to SAAMI specifications , will blow up a properly assembled Mauser rifle, I will most definitely call it BS! I believe you will to, actually you already have! I am sorry if I offended you, but I do not like half-assed analysis of complex strain systems. Will called it pseudo-calculations, that is a much more politically correct terminology, but it means the same thing. The proper, complex analysis wasn't done, for whatever reason, and a inaccurate, misleading, analysis is presented for review.



It may well also be that those reading the article are clueless as to what it is really saying. As I stated before I have not actually read the article so I cannot form an opinion about it. My statements on this subject have ALL been of a general nature, and not specifically addressed to Mr. Bekker's article.



It would be great if you could get him to post here. I would love to have an intelligent conversation about action strengths and weaknesses! It would be a delightful change of pace from the ordinary.



What action does the magazine article in question suggest should be used for ALL belted H&H magnums since they ALL operate at 62,000 psi maximum average pressure (that would be the 264 Win mag up to and including the 470 Capstick, and yes the ol' 375 H&H is in there too).



Will,



I like your last post, it said it ALL!



ASS_CLOWN

I know nothing about engineering but I am pretty adamant that a cz 550 in .458 lott would where out a few barrels before the action was stuffed....not that many would shoot out a .458 lott barrel at any rate.

Will,

Quote:

---

Technically speaking, shear strength is a material property

---

You are of course technically correct! I have found that many who post here are not technically trained so I attempt to use language I hope they understand; therefore, "strength" instead of the correct term "stress".

Due to the fact that the top locking lug of a Mauser M98 is split it has ~ 20% to 25% less shear area. This results in a ~ 20% to 25% increase in shear stress. Since, as you correctly stated Will, shear strength is a material property, this means that a Mauser M98 can only handle about 75% to 80% of the bolt thrust when compared to a design identical overal lug footprints but WITHOUT the top lug being split.

The majority of more modern dual opposed front locking lug designs have larger footprints, and not split top (or bottom) lug. This was done to increase the shear capacity of the bolt, i.e. reduce the shear stress, which allows for greater bolt thrust capacity.

Of course to be thorough, and there is absolutely no reason to anything if one is not going to do a thorough job of it, the abutments the lugs are supported by must also be considered, as well as the concentration of strain energies in both the top and bottom lugs and their abutments. The strain energies are of paramount importance because through their analysis we can understand best which lug/abutment carries the most load, and were the areas of fatigue and/or ultimate overload failure will first occur. Typically, the male locking feature will fail before the female. Of course this assumption rest upon both the male and female locking features being made of the same material and heat treatment.

Of course another MAJOR issue is fitment to abutments. If one lug is snug while the other has some small clearance an impact load could/will occur. Impact loading dramatically increases strain energies, and many steels (SAE4140 in particular) when heat treated to elevated hardness to not like impact loads i.e. they what is called low impact strength. SAE 8620 is far superior, as is SAE1340 (if you don't want to case carburize, which is expensive relatively speaking). The SAE 4300 series falls between 4140 and 1340 (actually 4340 is considerably closer to 4140 in impact strength meaning it is only marginally better). Of course if case carburizing isn't an issue then the good old aerospace standard SAE 9310 is the cat's meow. This stuff, SAE9310 that is, has very good impact strength.

I little less ambiguous, or shall we continue?

Would someone like to calculate the von Mises stresses on the bolt lugs and abutments of a Mauser M98? This would solve this silly argument in short order. By the way, I am not interested in performing these COMPLEX calculations, sorry.

ASS_CLOWN

FYI,

Arse is the southern Afrcia version of ass.

And I forgot to mention lawyers, but I guess that goes without saying.

Ray,

If it weren't for books and the ability to read them, there WOULD be a great many more ignorant people in this world!!

Why do insist that I am a troll? What have I done to deserve this title?

ASS_CLOWN

Jeffery Denmark,

The Selous rifle company has closed down as I said. I have no idea of the prices of Vektor Magnum Mauser actions but several members here have them and would be able to tell you how much they bought them for.

I shall wait for someone to tell you this and read their post as interestedly as you would.

Good hunting!

ASS CLOWN IS ONCE AGAIN SHOWING HIS CLOWN ASS, ALL HE KNOWS IS WHAT HE READS ON A DAILY BASES, GIVING NO THOUGHT TO ITS CORRECTNESS, JUST EXPOUNDED ON HIS NEWLY AQUIRED KNOWLEDGE AND STARTING ANOTHER ARGUEMENT AND WHEN YOU PROVE HIM FULL OF SHIT AS CHRISTMAS TURKEY, HE JUST GOES ELSEWHERE AND SPREADS HIS CRAP...

HE IS A TROLL GENTLEMEN, HOWEVER A FAIRLY POLITE TROL,THEREFORE BARELY ACCEPTABLE, MAYBE ...

Back to the subject, if the pressure is enough to shear the split lug on a Mauser, then the grand old M-70 and many others would come apart like a hand granade whereas the Mauser would puff up like a baloon, might even split a bit, but would not fragment sending sharpnel to the forecorners..

mehulkamdar

Thank you for posting the links.

Do you know the price of the actions or the barreled actions ??

Cheers,

Andr�

Jeffeosso,

I have not much of a clue what your last post was about (all that percentage stuff ????), but nowhere have I stated that a properly set-up mauser action is not strong enough for any of the H&H belted case derivatives.

By the way, I have ABSOLUTELY no intentions of going through and calculating the von Mises (combined stress) stresses acting on a Mauser action, particularly by hand!! If you would like to attempt to solve them Jeffe, I will be more than happy to share all the numerous equations needed to get the job done.

TheCoolGuy asked a simple question about why a mauser was not as "strong" as SOME of the mauser derivatives. I answered him, correctly as it has only to do with the ejector slot cut into the top lug of a Mauser, M1917, Pattern 14, M1903, etc. This slot is NOT present in a CZ550, Ruger M77, Win M70, Remington M700, Dakota M76, etc.

I suggest you reread my previus posts until you understand what I wrote. That goes for the rest of you too, except Will who seems to have grasped the message the first time through.

Will, I know what an "arse" is, but I am a jackass not a "butt". Or are you suggesting I am both a "butt" and a jackass?

ASS_CLOWN

Would the locking lugs on say.. a CZ 550 have similiar strength when compared to the Ruger's?

What type of steel are CZ's made out of?

Thanks!

From the now defunct website of a company that made good rifles on the Vektor Magnum Mauser actions on Mausers:
http://web.archive.org/web/20010410173818/www.selousrifles.com/actions.htm

http://web.archive.org/web/20010824233032/www.selousrifles.com/actfeat.htm

http://web.archive.org/web/20010419162135/www.selousrifles.com/futherinfo.htm

As an amateur, this is all I can post not knowing mroe than the experts here. Hope this helps.

Good hunting!

ASS CLOWN,
Because you did it the old fashion way, you earned it!!

Ray,

As long as you feel I earned it, then it is okay by me!

Dan,
I would truly appreciate it if you could post that sentence you referenced.

ASS_CLOWN

I couldn't get the page to come up but at least attempting to model this with a FE code is a great idea and should be more accurate than just a force and area calculation.



Though I have no experience in bolt failure, I just wonder whether that the bolt lugs along with part of the bolt body are just as likely to separate rather than the actual shearing of the bolt lugs from the bolt body.



I am not sure why only the inside diameter of the case is used to calculate the force on the bolt face, unless it is just assumed that the case rim flexes so easily that it has no effect.



I would assume that the big unknown in doing any of these calculations is knowing the force from the case on the bolt face (thrust), as opposed to the statement that the case contact with the chamber wall will sometimes reduce half of the pressure generated inide the case. Of course the worst case would be that all of the pressure generated is seen by the bolt face.