Durability: just how tough is the M9?

[praharin]

I have heard the stories of how tough they can be, but every M9 I ever saw while in the Corps was broken. I literally never saw one in use that didn't break. However, that was probably less than 10 of them. We used the M7 exclusively, so I have no personal experience, just casual observation.

So, what kind of abuse have you put an M9 through, and what brand was it?

Thanks,

[Mister Moon]

The M9 is (almost) unbreakable. The used steel is very good, very hard. My great friend Joe ANVIL know well the "hard" & difficult work on it. btw, me too.

[praharin]

Thank you for the input. However, I am looking for more specific information on what you have been able to put them through.

Based on my experience, calling them unbreakable is laughable. Please, provide some details and prove me wrong.

[Mister Moon]

http://www.youtube.com/watch?v=kqyHxZcrX0I&feature=related

[praharin]

That's interesting, and I have seen it before. The lateral bending is useful, but doesn't tell the whole story. The stress on a bayonet is going to be at the end of a meter long lever arm, not just the knife itself. Part 9 was also somewhat useful, but again, tests only the knife itself, not as a bayonet. I am looking for more information on how it performs as a bayonet. Specifically the Lan-Cay and Ontario models, since they tend to be the most readily available. I am really interested in the M9, since it will actually allow me to reverse the orientation of the blade, which I very much prefer in a bayonet.

Thank you for your input.

[O3SKILL]

I have heard the stories of how tough they can be, but every M9 I ever saw while in the Corps was broken. I literally never saw one in use that didn't break. However, that was probably less than 10 of them. We used the M7 exclusively, so I have no personal experience, just casual observation.

So, what kind of abuse have you put an M9 through, and what brand was it?

Thanks,

You answered your own question Devil. The M9 was not Marine "ABUSE" proof and is probably one of the main reasons it was never fully adopted by the Marines. As a bayonet/field utility knife the M9 is superior to the M7 and will serve you well if you take care of it and don't "ABUSE" it. Particularly so with the later models that you are interested in. Reading up I have seen stories where the ARMY had quite a few problems with the M9 early on, due to improper QC, heat treating etc.

I believe it was here. A gent posted that his unit in the ARMY was one of the first to get the new M9's in the 80's. His first shirt was looking one over in their Armory, accidentally dropped it and the blade snapped in two when it hit the deck. Needless to say that wasn't a good first impression :confused:

As far as bayonets are concerned it's pretty hard to beat the M7. Those things were absolutely beat to shit in the fleet and I never saw one break.

From a collectors stand point, I really enjoy both, however If your looking for a real world bayonet/field utility knife IMHO you would be better served with what the Corps is using today...the OKC3S.

[praharin]

I think I am gonna pinch some pennies and get the ZT9. M9 size with a full tang and Strider design in S30V. Pretty much a winner all around, to me :D

[Kurtis Dwight Davis]

Broken M-9's come as no surprise to me. I invented the impact resistant/modular design, as evidenced by U.S. Patent 4,458,420. The present form of the M-9 happens to be an ineffecient application of my advance to the art, and is guaranteed to selectively shear metal if enough stress is applied to the hilt. It will be interesting to see what Mr. Bill Porter and/or "Quarterbore" decide to share with you, with regards to information now sent.

[Oldsmithy]

Nothing is unbreakable, I know i break things for a living and do failure investigations on things that have. A tool is designed for a particular use and stresss, over do it and it will break. Of course the first thing peopel do when they get somethign like this is see if it will break, and if it can be thrown!! they then complain when it does and it can't, it is nice however to know th elimits of your tools.

Me i woudl take the Extrema Ratio but then it is 3 times the cost and Americans complain at their taxes already

[pwcosol]

I believe when the U.S. Government issues a solicitation for bids to manufacture certain piece of equipment, they normally provide the minimum standards to be met. Then it is up to the competitors to produce the best piece of equipment at the lowest unit cost, if they hope to win the contract. In the case of bayonets, they are not (nor ever will be) expected to be indestructible. However, a bayonet which is strong but tensile enough to withstand normal service use is all that is required.

The XM9 trials competition is a perfect example of this. Look at the number of failures, and examine the corresponding bayonets submitted. Plainly the majority were weakly constructed and had blades or other components which were too brittle or prone to breakage. The Phrobis XM9 was the most robust of the lot. Because of this, the Army opted to purchase the Phrobis regardless of the cost (and took a lot of heat for it, too!). I suspect had the Phrobis design proven as flawed as the majority, the Army would have rejected the entire lot, and either retained the M7 or held another trials at a later date.

One other point worth consideration is Phrobis researched, developed, & offered numerous improvements for the M9 to the Army. This was one of the concepts at the core of the Multi Purpose Bayonet System (MPBS) M9. Unfortunately Army thinking at the time had not evolved sufficiently (as is has now) to take advantage of this benefit. Had it done so, improvements might have been made to make the M9 an even better bayonet, and likely at no additional cost to the Army...

[Kurtis Dwight Davis]

Minimum standards for durability of the M-9 were carefully defined in the original contract. These standards were supposed to be verified with destructive scientific testing. When asked to provide the results of such lawfully required tests, the United States Army failed to do so.

[pwcosol]

That is an interesting fact. Guess it begs the question as to why the Army declined to release the data. That being said, Phrobis/BUCK undoubtedly did their own stress tests to ensure the bayonets did meet Army specs. We know from reports the tip of the bayonet as found on the prototypes was weak, and this problem was subsequently redressed in the production bayonets. I have read there were concerns about the fuller possibly making the blade weak, and the tang/rod may have also been an issue. The latter seems evident from the Phrobis product improved prototype held by one of our Forum members: http://www.quarterbore.net/forums/showthread.php?t=2900. I recall seeing another Phrobis P. I. M9 with what looked like a nylon hex rod in the grip as well. In addition, the insistence of the USMC wanting a solid-tang incorporated in the 1993 trials bayonets submitted by BUCK also shows concern over the threaded tang/rod.

[Kurtis Dwight Davis]

From my point of view, it seemed the Army wanted to sit at a desk and simply guess about the exact operation of the M-9 hilt. By doing so, they could avoid recognizing that operation of the hilt infringes U.S. Patent 4,458,420. Destructive scientific tests were the responsibility of the contractor, with the results being submitted to Army possession. After repeated requests for those results were made, it became apparent that they were unavailable, and certainly never relied on as per claim of infringement made with the United States Army Laboratory Command. These guys further ignored such scientific tests as submitted by me.

[Mister Moon]

U.S. Patent 4,458,420 Shear pin hilt for knife
Abstract
An impact-resistant knife hilt comprising a hollow handle containing a clevis with shear pin connecting the knife blade to a bolt passing through the end cap of the knife handle. Such a knife is readily assembled and disassembled by tightening or removing the bolt while the hilt with shear pin reduces the risk of blade breakage upon their impact.

Inventors: Davis; Kurtis D. (8530 E. 66th Pl. S. - No. B, Tulsa, OK 74133)
Appl. No.: 515200
Filed: July 20, 1983


http://www.freepatentsonline.com/4458420.html

http://cgi.ebay.ph/280-SWORDS-KNIVES-SWORD-RELATED-PATENTS-ALL-CD-/270319872663

[pwcosol]

Thanks M.M. for posting the link to KDD's patent. I reviewed the patent description & accompanying photos. The clevis w/shear pin arrangement is an interesting concept to allow ease of assembly, repair, and retention of the blade to the guard & other components. The general idea certainly shares some similarities with the Phrobis design. However, the threaded blade tang and rod utilized to secure the blade to the grip/pommel do differ substantially. Whether it does or does not to the degree it might be considered a violation of patent 4,458,420 would be up to a court of law to determine.

[Mister Moon]

...yes.
We are not... judge(s)

[Kurtis Dwight Davis]

The true test of infringement is whether or not one or more of the '420 claims may be applied to a fully assembled M-9 hilt, while said hilt is under pressure, or put to some kind of work. Furthermore, patent infringement considers much more than the title of the patent, or comparison of elements. What exactly the Patent Office agreed to, and how it may be applied to actual M-9 performance is what counts. However, there will be no judge/jury, because we all had our 1st amendment right to petition for redress of grievance abridged, and it was Ronald Reagan who signed the law. Of further note is the fact that any personal correspondence received from the infringing party, before infringement, may be considered evidence. Unfortunately, it is not convenient to supply you with such evidence---copy has been sent to Mr. Bill Porter. Taking one small part of '420, while neglecting all the other technical language therein, will not allow adequate comprehension. Thank you for an opportunity to speak up.

[Mister Moon]

Thanx for these information.

[Carlo]

That being said, Phrobis/BUCK undoubtedly did their own stress tests to ensure the bayonets did meet Army specs.
Yes, I also think so.
In the article posted on this topic (I just updated the download link) http://www.quarterbore.net/forums/showthread.php?t=2485
there are reports and pictures of the machines used during the testing.
http://img80.imageshack.us/img80/4130/clipboard02fs.jpg

[Kurtis Dwight Davis]

Interesting picture. It's too bad the United States Army was unable to provide copy of actual test reports, as repeatedly ask for. Even worse would be the fact that the United States Army Laboratory Command completely ignored such results, even if they did in fact exist.

[Kurtis Dwight Davis]

Please be advised personal correspondence from the original M-9 manufacturer is now available on this website. Go to photoserver, scroll down to the bottom of the page, and look under new photos. Said correspondence was received in response to solicitation of license agreement for U.S. Patent 4,458,420. This represents evidence of a unique, untold part of the M-9 history, and is available only on "Quarterbore". Such correspondence was made part of an official investigation, conducted by the United States Army Laboratory Command; as such, it would, in theory, be available through Freedom of Information Act request.

[porterkids]

The true test of infringement is whether or not one or more of the '420 claims may be applied to a fully assembled M-9 hilt, while said hilt is under pressure, or put to some kind of work. Furthermore, patent infringement considers much more than the title of the patent, or comparison of elements. What exactly the Patent Office agreed to, and how it may be applied to actual M-9 performance is what counts. However, there will be no judge/jury, because we all had our 1st amendment right to petition for redress of grievance abridged, and it was Ronald Reagan who signed the law. Of further note is the fact that any personal correspondence received from the infringing party, before infringement, may be considered evidence. Unfortunately, it is not convenient to supply you with such evidence---copy has been sent to Mr. Bill Porter. Taking one small part of '420, while neglecting all the other technical language therein, will not allow adequate comprehension. Thank you for an opportunity to speak up.

Mr. Davis has sent me an impressive amount of information on his patent. My intention is to scan and post the information here for all to review. I just haven't had the time to do it yet, but it will get done.

[Kurtis Dwight Davis]

Take your time Mr. Porter; I've been waiting for over 20 years, so no need to hurry! I truthfully and sincerely thank you and "Quarterbore" for giving me an opportunity to share what I know about the M-9. Please be advised that personal correspondence received from the original manufacturer is now posted on this website. Go to photoserver, scroll to the bottom, and look under "new photos". Every single day, for 25 years, I have hoped and Prayed for the current opportunity.

[Kurtis Dwight Davis]

[QUOTE=Mister Moon;22923][B][SIZE="4"]U.S. Patent 4,458,420 Shear pin hilt for knife
Abstract
An impact-resistant knife hilt comprising a hollow handle containing a clevis with shear pin connecting the knife blade to a bolt passing through the end cap of the knife handle. Such a knife is readily assembled and disassembled by tightening or removing the bolt while the hilt with shear pin reduces the risk of blade breakage upon their impact.

"Having thus described the preferred embodiments with a certain degree of particularity, it is manifest that many changes can be made in the details of construction, arrangement, and fabrication of the elements and their uses without departing from the spirit and scope of this invention. Therefore, it is to be understood that the invention is not limited to the embodiment set forth herein for purposes of exemplification...." (Language from Patent 4,458,420)

The exact idea approved by the Patent Office is not limited to the drawing(s) or abstract, but is expressed by EVERYTHING the document says. To prove infringement requires the entire description be applied to a fully assembled M-9 hilt, which is subject to destructive scientific testing. When that is properly done, claim #1 fully applies to M-9 hilt operation. This result combines with modularity (assembly/disassembly) within and about the same hilt which also provides repairable, selective metal shear. Exactly who had the idea first, and first approached the original manufacturer and U.S. Army, also constitutes lawful evidence of infringement. EVERY SINGLE BIT OF THIS WELL KNOWN PROCEDURE WAS AVOIDED BY THE U. S. ARMY.

Thank you for an opportunity to share my experience with the M-9 Multipurpose Bayonet System.

[Kurtis Dwight Davis]

The original contract required Finn to yield two types of test results---those which assure minimum standards, and also results of destructive tests. Finn claimed to have submitted all required results, but the Army failed to provide any such information, even after numerous requests. The only way to determine exactly what the M-9 rod does is to actually test it and see. Davis took two M-9's to a laboratory and had both subjected to destructive testing, which reveals that the rod and grip first deform, and eventually the rod selectively shears the pin like end of the tang. Moreover, such selective shear is repairable without welding, by replacing the rod with a 3/16 clevis. To this end, the test samples, engineer's reports, and video tape of the destructive testing has been sent to Quarterbore Super Moderator Bill Porter (dispatched to his location via U.S. mail, over one year ago).
It should be further understood that the '420 invention involves more than selective shear by some attachment--the attachment must further allow for modularity, and all useful benefit which arises. Prior art cited by Davis includes Dickerman, which expresses the M-9 rod/threaded tang. If such rod is used to arrive at impact resistance, conjoined with modularity, in the hilt of a knife, it belongs to Davis (most especially when the rod is proven to selectively shear metal, which can be repaired without welding).

It is my conclusion that the United States Army was either too stupid to understand any of this, or too much a coward to admit it if they did.

Thank you for opportunity to share experience with the M-9 bayonet.

[Kurtis Dwight Davis]

Please be advised that Dickerman prior art, cited by Davis in U.S. Patent 4,458,420, is now available for your analysis. (photoserver) This prior art is a matter of offcial record, which cannot be altered. Please take a close look, and notice it is Davis who associated an impact resistant, modular hilt , to the M-9 method of construction.

Here is concrete proof that Davis fully anticipated use of a connecting rod as opposed to a clevis, in order to bring about impact resistance conjoined with modularity, in the hilt of a knife. It is generally understood that a patent defines what IS invented, not the opposite.

Thank you for opportunity to share experience with the M-9, perhaps the greatest bayonet in world history.

[StuartOutfitting]

Hello,

I own an Ontario M9 which came relatively unused, with chipped tip and was bent (very slightly) around where the tang meets the rod - I suspect, with tang not providing a full thread for the rod to mate with, that this is due to the teeth of the thread jarring and starting to mis-align.

But all merit to the M9 for trying atleast, because the other day I started to actually destroy the wire cutting surface on the bayonet with relative ease by cutting 2mm diameter solid High Tensile fencing wire, and servere burring appearing on the cutting surface afterwards, but only mild (if any) burring appearing on the sheath's cutting surface. Until the 2mm High Tensile, she cut soft (solid and two-strand barbed) and two strand high tensile barbed wire with ease and quite well.

The steel used in them, as I've just ground a more shallow edge onto the cutting surface which had the least hollow grind to bring it up to par with the one that had a better hollower grind, I know is pretty hard, comparable to something used in quality axes or wood chisels.

I believe it would require definitely time and effort to put a fine, and extremely sharp edge on an Ontario M9, which is probably not what a marine wants to hear being that I heard they like SHARP when a simple edge will gut most of your enemies.

I wouldn't buy a M9 again where that the tang is two piece construction, being that the tang which threads into the rod offers so little thread to do so with - Overkill is better than underkill, would you cut a flat bolt that has a tensile strength of exactly 1 ton and use it to hold 'a ton'?

[pwcosol]

Interesting observations on your Ontario M9. I do not have a copy of the solicitation by the US Army specifying what type & gauge of wire the M9 was required to cut. However, double-strand barbed wire would have been one. Regarding the bend on the blade tip, (at least from examples of Phrobis/BUCK manufacture I have seen), the tip would tend to break clean rather than bend.
You mentioned the blade appeared bowed or loose; possibly because stress may have caused the threaded tang to come out of alignment with the threaded tang rod. I believe this potential weakness in the design was why both Phrobis & LanCay developed "solid tang" prototypes (primarily requested by the USMC) for trials evaluation. One possibility is the threaded tang & rod on your Ontario M9 might be close to minimal spec for fit. In addition, the tang nut is required to meet a torque spec when tightened. If the nut was not secured sufficiently, this might result in the problem you reported when subjected to stress.

[StuartOutfitting]

No, not the tip of bayonet was bent, that was chipped, in a fashion similar to if someone had just ground the tip of with a bench grinder.

Right where the tang threads into the rod was where the bend-thread bind was, making the rest of the bayonet extending beyond the handle look slightly offset in angle to the handle. A funny thing occured while I was reassembling the handle.
When I tightend the bolt which holds the handle assembly of the bayonet on to the rod right up with only an alan key, I heard a thread-cracking sound as if the rod was tightening more onto the blade and now everything looks straight! Unlike when I first took the bayonet out of the sheath.

All this has me concerned about the 'flat' thread employed, I would of gone with a full thread myself!

^ ^ And appending to my original post, I would buy and use M9s if I could get them for around $40 bucks, but I would be happier with my investment of $150, if they did have a full thread, or even better, a full tang like the M7!

P.S. Did you recall those army solicitations mentioning anything about reinforced Razor Wire?

Thanks.

[pwcosol]

Regarding the tang, look at some of the earlier threads under BUCK M9 or LanCay. You will find some references to the solid-tang trials bayonets. Here is one link: http://www.quarterbore.net/forums/showthread.php?t=2160 The complete thread design appears to be used on the BUCK examples. However, except for the one pattern still utilizing a screwbolt to secure the blade/pommel cap, they were secured by a rivet (BUCK USMC) or welded (LanCay USMC/USA) and not meant to be serviceable.

I would agree $150.00 is a lot of money for a bayonet if it fails in it's purpose. Ontario M9s are usually available in new condition and can be had for around $100.00 on sites like Ebay. In addition, often moderately used examples turn up from government DRMS auctions for about $25.00 less than that on the same venue. IMHO if I wanted one M9, I would look for an excellent Phrobis 4-line. You should be able to find one for around the $150.00 paid for the Ontario. Regarding the wire the M9 was required to cut in the 1986 trials, don't have the specifics (although I thought someone had given me a strand). I am pretty sure Bill Porter (one of our M9 Gurus) may have the answer...