m/41b Swede Sniper Catastrophic Failure

[drklynoon]

I might be off the mark here but I don't think so. Hasn't the swede reciever had a groove machined off the top of the reciever? I think that groove goes al the way to the barrel face. Added to a "weaker" mauser action, any problem could be magnified.

[swheeler]

I think SEE is as good of an explaination as any for this rifle exploding.

[WineMan]

Bret,

I have no qualms that the 6.5x55 is a balanced cartridge. My reference to "on the edge of overbore", is just that: it is on the edge. To me when the cartridge performs best with slower powders or we try to improve performance with slower powders is a requirement for overbore. Compared to a 6.5-06, which most would describe as overbore, Hodgdon's MAX load of IMR 4831 is 1.5 grains less for the Swede than the 6.5-06 for about 2,700 fps with the same 140 grain jacketed bullet. For the 160 grain jacketed bullet the difference is only 0.8 grains. This is an average difference of 2% so fairly close to an agreed overbore cartridge. I am sure there will be differences of opinion and agreement with my statement. My intent was not to pigeonhole the Swede, but to just mention that like in most accidents it is a cascade of factors not just one.

Wineman

[BD]

To me, "Overbore" has a sort of negative connotation implying higher pressure, more rapid throat erosion and shorter barrel life. As the 6.5 x 55 operates at around 50,000 psi, and has an average barrel life of something like 100 years , I have a hard time thinking of it in the same terms as the .220 Swift

I'd describe it more as a "Just right bore"

BD

[MtGun44]

Linotype,

Not to be too obsessive, but the comment "Every round fired induces some amount of
stress on the assembly. As pointed out, chamber and bore wear at more factors to
the stress. In time, it all adds up." is absolutely, scientifically proven to NOT be the case
for stresses below the 'fatigue limit' in steel. The problem usually comes when a machine has a
flaw such as a scratch, gouge, machine mark, stamped number or letter, etc which locally
concentrates the stresses to higher than intended - exceeding the infinite fatigue life stress
level locally and leading ultimately to a total failure if enough cycles are completed.

For steel alloys with cyclic stresses below a well defined stress limit (usually about 50% of
yield stress) there is NO maximum number of cycles to failure. Failure will NOT occur, even
a many, many millions of stress cycles. The topic is extremely important in engineering
design and many people have been injured and killed over the years due to ignorance
in this area, so that there has been a lot of well funded research in the area. The key
point is that stress in steel less than the critical value is totally harmless and is NOT
causing some sort of invisible damage. Above the critical value, it IS causing damage, but it
is not invisible, except very early in the process. The fatigue process is a microscopic cracking
and steady, incrimental crack growth every cycle. These cracks are detectable with non-
destructive testing methods many, many cycles prior to a catastrophic failure. A fatigue cracked
gun part that is anywhere near failure can be detected with dye penetrant or magnetic particle
inspection methods, and often with an extremely good inspection with 10X magnification. It
CANNOT fail without a crack, if it is a fatigue failure. A sudden overload failure is a totally
different situation. Examination of the fracture surface will identify which type of failure occurred.

Note that aluminum has NO infinite fatigue life limit stress level and ALL aluminum structures
WILL eventually crack if cycled enough times, regardless of how low the stress level is. BUT
they still will crack LONG before they suddenly fail, and can be detected with non-destructive
inspection methods like dye penetrant inspection.

Bill

[swheeler]

The slow IMR single based powders, most notably IMR4831/sold as surplus 4831 when I started loading are notorious for this in greatly reduced loadings. It is noted in reloading manuals 40 years ago, guess until psi testing got more prevailant they never understood why, what was going on. I remember reading the warnings in IMR handloader guide when 7828 was introduced mid 80's do not reduce listed loads. I do not believe in flammable solids-as in smokeless propellant- detonating like a class A explosive, be it single base or double based powder, but I do however believe in the bore obstruction theory, although that looks to be closer to fact than theory now. SEE senior

[linotype]

"Not to be too obsessive, but the comment "Every round fired induces some amount of
stress on the assembly. As pointed out, chamber and bore wear at more factors to
the stress. In time, it all adds up." is absolutely, scientifically proven to NOT be the case
for stresses below the 'fatigue limit' in steel. The problem usually comes when a machine has a
flaw such as a scratch, gouge, machine mark, stamped number or letter, etc which locally
concentrates the stresses to higher than intended - exceeding the infinite fatigue life stress
level locally and leading ultimately to a total failure if enough cycles are completed."

Bill, first and foremost, let me defer to your knowledge and experience on this topic.

My comment was intended more to agree with the SEE topic.
I may be mistaken, but I feel that vintage firearms should be handled with consideration, such proper safe load ranges, and to be mindful that there will be wear on the components over time.

I am not suggesting that the firearm will fail due simply to stress. Considering the age of the firearm, wear from usage, and lacking a knowledge of all the previous history of the firearm, an owner should follow a routine of safety inspection and reasonable use. The unexpected failure may happen, but I expect that it would be due to carelessness or mishandling. Because these old firearms were well designed and well built, does not mean an owner should be reckless or foolish about reloading.
I agree with you about the longevity of a machine operating within design tolerances. I have seen this in auto engines and machining equipment. It all comes down to good design and proper care.

[Tokarev]

I am always astonished by the folks who throw around phrases involving 'safety inspection' because I have never found a gunsmith capable of that or simply willing to take responsibility. Have you?

[Mike Venturino]

I found this passage on the last page of the book THE MAUSER BOLT ACTIONS: M91 through M98: A Shop Manual by Jerry Kuhnhausen.

It reads, "Paul Mauser elected the simplest, most logical solution which was to design a practical, common sense rifle action with features that overcame the existing state of the brass metallurgy art and the limitations of the then readily available low/medium carbon industrial steels. What is key here, is that the M98 action was engineered with the above metallurgy and almost every other imaginable field use and manufacturing problem in mind. Mauser designed and produced a case hardened action that was tough, but not brittle, so that it would not shatter when stressed or when high pressure gases were suddenly released."

What I read is that in pre-Model 98 actions if a case failed then the gas was likely to shatter the action.

Because I have two defective Remington-Peters 6.5x55mm Swede cases that came from a single bag of 100 cases, what I fear happened here was case failure.

MLV

[Larry Gibson]

Mike

Look at the primer pocket and extrusion in the extractor slot. Case failure does not do that. Over the years i have had numerous case head sperations and case failures in the web area from faulty brass. I also have examined quite a few other case failures and several documented SEEs. Got some gas back int the actions but never seen blown primer pockets or extrusion like that into the extractor slot. What you see there are obvious signs of very high pressure and either are from a very serious overload or an SEE.

BTW; how are your 2 R-P cases defective?

Larry Gibson

[madsenshooter]

Could very well be a case failure, I have some SL56 brass that has a combination of thick walls and soft head. They weigh about the same as an LC case, but putting the same charge into the SL as the LC will cause the SL to blow the primer, and extrude a bit into the extractor of my M1. So a soft head can give premature pressure indications like you're seeing. They were only softer than the LC, what if some got by that were near dead soft? The rest of the failure could be attributed to the case head size of US made 6.5x55. The dimensional differences are the same that Hatcher warned about when using 30-06 to make 7.7 Japanese. Having said all this, I voted for SEE in the poll, but with these thoughts nagging me.

[Larry Gibson]

After thinking it over, the case obviously failed. So the real question here is was the failure induced by poor quality of the case where in it failed with a "normal" load or was the failure from extremely high pressure caused by SEE?

Larry Gibson

[Mike Venturino]

Larry: We have to take photos this week for deadlines so I'll have my wife take photos of those two cases and post them here. I've never seen new cases that look like them.

By the way has anyone tried putting 39 grains of H4350 in a R-P 6.5mm Swede case? There's not much room left over.

This stuff is very puzzling. Also worthy of note is that Hornady's manual in the 6.5mm Carcano section recommends ONLY Winchester LR Mag primers. I asked them before loading if Federal 215s could be substituted cause I didn't have any WLRMs. They said it was ok.

Also I like that fellows suggestion about using Prvi brass of the correct dimension. I'm hunting some of that up too.

MLv

[Mike Venturino]

Larry: You hit the nail on the head there.

Another thing that puzzles me is that we're seeing this with several 6.5mm Swede rifles. Are we just hearing about them and not the other rifles types and calibers that let go or is this thing happening more often with Swedes of late?

If so there are other factors involved about which we need to know.

Way back in the '70s there was a powder from Hodgdon named H205. I read in one article where it was blowing primers in 6mm Remington with loads recommended in manuals. About that time I got a .300 H&H and used it in that Model 70 with complete satisfaction. Then I decided to try it in my .257 Roberts Model 54 with above a starting load but certainly not a hot one and the primer blew on the first shot. It was discontinued shortly thereafter. I still have the rest of that can around here somewhere.

Back in the heyday of the cowboy action game lots of single action revolvers were blowing up. Even the vaunted Ruger Blackhawks and Vaqueros with their big cylinders and strong frames. I have several photos of such that people sent me. Some of the powder charges SAID to have caused the destruction wouldn't have been an overload even if double charged. When people asked me about it I had to say that I had not a clue but that it was best to not try to make a .45 perform as a .38.

To the best of my knowledge no one ever answered the question as to "why" sufficiently. At least some good came out of it with the introduction of Trail Boss.
MLV

[Larry Gibson]

Mike

Appreciate your efforts on the photo's, no problem with the wait.

I've seen and heard numerous people quote Kuhnhausen on that. It is true of the M98 but ponder this; Most M96s were made during the same time as M98s. Do we really think that they would have used inferior steels and heat treatment in one when the better steels (especially the Swedish steels) and heat treatment were available? Hardness testing and research has shown the manufacturing techniques for both actions to be the same. Granted the design of the M98 is such that it will better handle the escaping gas from a case failure. However, M98s come apart just like the M96s pictured here when an SEE happens.

We have seen on the internet in the last 10 years or so numerous actions (M70s, Weatherby's, Remingtons, M1As, Marlins and Rugers along with several milsurps) that have beed destroyed as the result of SEEs. Dutch just seems to be zeroed in on the M96 for this as some zero in on the LSN'd M1903s when someone asks about shooting them.

Remember, SEE has been proven and is readily replicated. That takes it out of the "theory" realm and puts it into fact. The "wave" and "detonation" theories are still theories as no one has been able to replicate them in controlled, measurable circumstance. The 6.5 Swede is very susceptible to SEE because all the conditions (long throat, use of reduced slow burning powders and possible rough throats, etc.) are there. The 25-06 has always been susceptible with light weight bullets, a reduced charge of old 4831 and an eroded and rough throat originally cut for the longer 117/120 gr bullets. The smaller caliber Weatherby's such as the 7mm are also very susceptible with light weight bullets and reduced or too slow burning powders. Again, those conditions, what causes SEE and the results are documented and proven....not theory but proven.

The "heyday" of cowboy action shooting with reduced loads was pretty much the same as with PPC a few years earlier. Numerous cylinders were burst and top straps lifted off K frame S&Ws with the 'classic load" of 2.7 gr Bullseye under the 148 gr HBWC. This seemed to be occurring all of a sudden with much frequency. Wave and detonation were thought to be the causes. However, Hercules and S&W did a very exacting research of the problem. S&W did a thorough study of several of the revolvers involved and determined it was not failure or defects of the revolvers but very high psi which caused the failure. They found there to be no indication of pressure problems with that load. They found a double charge while higher psi, was still not enough. However, a double charge with a HBWC seated too deep did produce potentially high enough psi. A triple charge did also and if the bullet was seated too deep then the psi were quite enough to take apart a S&W K frame. They then tracked down the suspected loads to whom and how they had been loaded. Turns out the culprit most often was the inline progressive C&H press. It is real easy to double or triple charge a case with one of those. The marketing and use of those C&H loaders coincided with the rash of blown up revolvers. Subsequently the C&H loaders were discontinued. Point here is with the advent of semi progressive presses it is all to easy to double or triple charge a case, especially a large volume one like the .45 Colt, with some of the "said used" powders.

A friend of mine recently blew a case in a Tauris M1911 .45 ACP. Fortunately it damaged the magazine only. He had used my suggested load of 5 gr Bullseye under a 200 gr cast SWC. He blamed my load for the problem. He had loaded the rounds (200) on a Dillon 550B in another friend’s gunshop. I ask him if he was interrupted at all during the loading. He said he was that people were coming and going and he was BSing with the gunsmith. I then pulled the rest of the bullets (a little over 100) and found one loaded with 8.5 gr of Bullseye and one with a full 10 gr of Bullseye. He was astonished to say the least. We then repared to my Dillon 550 and I watched him load 50 rounds. During that he double short stroked the handle twist because he didn't get the bullet started straight in station 3. The result in each instance was a charge of 7.5 - 8 gr in the case. Now that he wasn't so about his own ability he remembered perhaps not rotating the star a time or two and thus probably double charge the .45 ACP case with 10 grs. He also recalled a couple rounds where the bullet seemed "hard to seat" which was probably the double charges rounds. So it wasn't the load, it was the "loading' that was the problem.

My point Mike is how many cowboy action shooters use progressive presses to load their ammo? You think perhaps they might have done the same thing? I know I have learned not to "short stroke" the handle on my 550B because it can add more powder, especially with the shorter pistol type cartridges. I was just loading 600 .30 carbine rounds two days ago and had it happen. It's why I got a Dillon SDB to load most of my handgun ammo with; it automatically rotates the shell plate so a double charge is very difficult to make happen.

Anyways, always good chatting with you.

Larry Gibson

[Mike Venturino]

Larry: Right. Visiting is always enjoyable. I wrote a longer post to you and this stupid computer lost it when I was trying to enter it. (Then again I may be the stupid one instead of these computers!)

Anyway I have to agree about progressive presses. I don't attribute all blown handguns to them but it does seem they are involved in many instances. Back in 1991 I blew up a 1914 vintage Colt SAA .45. I didn't (still don't) like to think it was my own error that caused it but I admit to loading the ammo on a 550B. Two hundred rounds were put together and the revolver let go on #6. Wasn't a bullet stuck in the bore because I was shooting at a dueling tree and all five of the first cylinder full swung paddles. I pulled bullets on the other 194 rounds and no powder charges varied more than a couple tenths. Still......

Now I use Square Deal Bs for .45 ACP and 9mm to feed my subguns, but for my other full-autos in 7.62x25mm, .30 Carbine, 7.92x33mm, and .303 British I load everything the old fashioned way - one at a time.

What amazes me most is how often no one gets injured by these accidents - not always but often.

I do want to clarify one point. In his book Jerry Kuhnhausen didn't say anything negative about steels. His reference was to poor brass metallurgy in bygone days and that the '98 Mauser handled leaking gas better than previous designs.

Anyway, I better get to work.
Mike V.

[Larry Gibson]

Mike

I wasn't criticising Jarry's book at all, sorry if it sounded that way. I was criticising the misinterpretation of that by many. You are right, of course, about the brass metallurgy as it was in it's infant days back then. They had lots of problems up through the '20s or so before they seem to have got it right. If one reads hatcher thoroughly it was the defective case metallurgey of some of the WWI '06 ammo that caused most of the problems with LSN '03s. With good ammuntion of the correct kind (too many reports of 8x57 being fired in '03s back then) there didn't seem to be the problem.

Speaking of H205 I was involved in one mishap with it back in the '70s and it's what really sparked my interest in SEE. Friend had a very nice long range 280 Remington. Couldn't get factory brass or loaded ammo at the time so we were necked down some new R-P '06 cases leaving a slight crush fit on the new shoulder. The '06 shoulders were a little back and needed to be blown forward. We had developed what had been a good load in the 40 .280 cases he had. It was a 100% loading density under the Sierra 168 MK. So we figured a case full in the formed '06 brass would work fine. It was 2-3 gr less powder. On the 4th shot the left hand mauser M3000 action gave way, not complete destruction but the bolt was ruined and I had to remove the barrel before we could get the bolt open. The chamber was also swelled. the 1st three shots went into just under 1" at 200 yards (we were confirming the zero) and no idea where the 4th shot went as the bullet wasn't in the barrel. The R-P '06 case was almost identical in appearence to the 6.5 R-P case posted. Fortuneately my friend was not injured either. With in a month the recall notice came out recalling H205. Don't know whether it was the H205 or the fie forming '06 cases with it but I (actually we) don't do that with slow burning powders anymore either.

Having used an old C-H inline press, several 450 and 550s, a couple SDBs, the RCBS and the Hornady progressives one thing I've learned is to be careful and pay attention. If I am interupted or need to stop for a while I finish loading all the cases in the shell plate before stopping. My wife interrupts me all the time and I aggrevate her because, before I talk to her or pay attention to her, with the 550B I rotate the shell, don't have to with the SDB, set a bullet on the charged case and put a new case in station 1. I've explained the potential hazards if i don't but after 20 years she is just getting used to it.....I guess.

One of the benefits of retirement....I can ramble on.....

BTW; I thought your article Bullet casting basics was excellent and should be pointed out to the new cast bullet shooter of which seem to abound these days.

Larry Gibson

[Dutchman]

The 6.5 Swede is very susceptible to SEE because all the conditions (long throat, use of reduced slow burning powders and possible rough throats, etc.) are there.

Neither of these two rifle failures were using a reduced slow burning powder. Both load levels were within published limits. A "reduced" load would be one below a published minimum load, IMO. You can argue about the burn rate of the two powders and while they lean more towards slow than fast I see no good evidence the burn rate was a factor here.

Neither of these rifles have any indication of a rough throat. You are introducing what you purport to be valid factors because they may have been valid factors in other cases at other times in other rifles. There is no evidence to support rough throats in either of these cases.

A good investigator considers all the factors and mulls over the possibilities. You have dismissed defective brass from the get-go despite multiple (that's more than one) reports of defective Remington 6.5x55 brass and repeated your S.E.E. theory ad nauseum.

The tangible evidence points directly at defective brass. By publicizing the fact that we have concrete proof of defective brass we may be able to save someone else's rifle and/or save someone from injury, the shooter or an innocent bystander.

To some readers your continued and repeated, along with unrelated "supporting" argument, could well cause some inexperienced handloader to dismiss the factual evidence of defective brass as being a valid cause or viable hazard in shooting Swedish Mausers using R-P brass.

I find oppositional conversation to be a mind game of the pathologically dysfunctional person. It proves nothing. It doesn't make one right if his is the last word. You've stated your opinion repeatedly. In the interest world peace and global climate change (excessive methane gases) move on.

p.s. You most certainly have trashed Kuhnhausen's Mauser book in the past. You stated your contemptuous opinion of his work in response to my quoting of his statement about the relative weakness of the 1893 Spanish Mausers in 7.62x51 Nato.

If one reads hatcher thoroughly it was the defective case metallurgey of some of the WWI '06 ammo that caused most of the problems with LSN '03s. With good ammuntion of the correct kind (too many reports of 8x57 being fired in '03s back then) there didn't seem to be the problem.

Well, this thread was about Swedish Mausers. We'll get into this subject of the low numbered 1903 rifles in another thread and another time.


Dutch

[PAT303]

In Australia both swedish mausers and Lee Enfield rifles are used on a weekly basis by thousands of shooters and in both cases it is uncommon for users to have American manufactered cases as in both types they are undersize and headspace and swelling are the end result.The case that it most common are Privi manufactured ones as they are of excellent quality and dimentionaly are very close to original specs and by far the most common powder used in both calibers is AR2209,Hodgden 4350,40grns under a 140grn bullet in the swede and 45grns under a 174grn in the enfield.In Aust we have had swedes for 30+ years and I can't find blown up rifles or any history of blown up rifles here and the one thing different between our rifles is we have always had a supply of European cases that are made to the correct spec. Pat

[swheeler]

Who says RP6.5x55 brass has the SAME base dimension as RP 06 brass, am still looking in notes, but I DON"T THINK SO! Come on somebody has to have a NEW UNFIRED lot of each, if I remember correctly, when I measured it, the 6.5 brass was about .010" larger just in front of the extactor groove than RP 06 brass was, .474 v.464. Let us not perpetuate more urban myths, gawd knows there are enough. My goodness- double base powders detonating like class A explosives, lead vaporizing at 750* F, burning all the tin out of an alloy if you heat to over 750*. Lets NOT let the voice of inexperience rule the air waves. OF COURSE THE BRASS GAVE OUT< IT'S THE WEAK LINK IN THE FIREARM, ANY FIREARM.