Recent Blow-up of a Sako 85

[guntech]

Several years ago I posted pictures of a Sako stainless blow up that occurred on Vancouver Island while using factory ammo...

Stainless steel during production can develop structural flaws. It is of great importance the steel being used for producing barrels and actions be free of these inclusions... they do happen from time to time and manufacturers are responsible.

Pictures from that time...

 

[South Pender]

That's very helpful, guntech. What were the circumstances of that blow-up? Was it determined that it occurred with normal factory ammo and with no possibility of a barrel obstruction or other "user error" that could have contributed?

From my earlier post (#44), we see that the person who first posted (on another forum) about this incident wrote the following"

"The only thing that I can think of is Ammonia corrosion and stress cracking of steel and brass alloys. With all the ammonia based cleaning agents ( used to clear copper from barrels) I worry about the ammonia getting into the action and when combined with high humidity, which we have in BC its a recipe for disaster. I have removed all ammonia containing solvents from my gun room !"

To me, this ammonia hypothesis seems unlikely. The existence of structural flaws in the stainless steel seems much more likely, and would jibe with the explanation of the earlier (2005) blow-ups of stainless 75s (given in Post #44).

For what it's worth, the present blow-up evidently occurred at the Prince Rupert Rod & Gun Club.

 

[Suther]

Now that is a case that looks like it blew up a gun!

 

[guntech]

The barrel let loose due to something like sulphur inclusions formed when the steel was made... Sako diagnosis...

As I said earlier this flaw in stainless steel is a known problem...

Ammonia cleaners are not the problem.

 

[Snowy Owl]

Very very interesting. I am eagerly awaiting the rest of the story and a plausible explanation for that specific incident of a Sako 85 stainless steel action blow-up.

 

[Bfranklin]

The fact that there was absolutely no barrel damage, yet the action was in many pieces, suggests that it is at least possible, if not commonplace.

"Commonplace"

Good grief.

 

[South Pender]

"Commonplace"

Good grief.

Apparently, I wasn't clear enough with that comment. What I meant is that it would appear that it is possible to blow up a gun without any barrel obstruction, but is very unlikely.

Not sure if or when we'll get more information about this current incident. It could be a while if we have to wait for some explanation from Sako or Beretta. Given all we've seen here, the faulty stainless steel explanation (such as the existence of sulphur inclusions noted by guntech) seems like the most likely--particularly since it was seen as the cause of similar incidents in 2005.

 

[iron cat]

The barrel let loose due to something like sulphur inclusions formed when the steel was made... Sako diagnosis...

As I said earlier this flaw in stainless steel is a known problem...

Ammonia cleaners are not the problem.

I remember the Sako barrel issue clearly.
It was determined that a bad lot of stainless blanks got past their QA/QC . There was a big advertising link that posted the serial numbers in question.
Two fellas I know had bought 338 Lapuas that year. But both of their rifles were not in the suspected serial number batch.
Both were bought from different dealers .
Cat

 

[Why not?]

you can chamber a 300 win mag in a 338 win mag and you will a perfect fireformed 338 brass once shot...the same was done with a 300 win mag into a 375 ruger ...i doubt you can feed a 338 win mag in the 300 win mag rifle.

No you can’t.

well i did. maybe the cut was different but i did.

Looking at the cartridge drawings with dimension and measurements, even the rammy-est guy could not make it happen. You'd physically need to drive the bolt home with a hammer to (maybe, in theory) make it fit once while damaging the rifle in the process.

You definitely cannot chamber a 300 Win in a 338 Win chamber. I think he may be thinking of the time he purposely fired 300 Win Mag ammo in his 375 Ruger as an experiment.

Ted

 

[Why not?]

You could do it with a .308 Norma, 7 Rem or .264 Win mag though. Thats probably what he was thinking.

You would have to really try to get a 308 Norma into a 338 chamber. The shoulder is almost a tenth of an inch further ahead.

7mm Rem and 264 Win definitely will work.
Ted

 

[BattleRife]

2. ALF, the poster on that thread, noted:

"The only thing that I can think of is ammonia corrosion and stress cracking of steel and brass alloys. With all the ammonia-based cleaning agents (used to clear copper from barrels) I worry about the ammonia getting into the action and when combined with high humidity, which we have in BC its a recipe for disaster. I have removed all ammonia containing solvents from my gun room!"

I've never heard about ammonia having this effect on steel, so don’t know what to make of his speculation. Is this a possibility?

ALF has clearly got his degradation mechanisms confused in his head. He seems to be taking ammonia stress-corrosion cracking of brass and extrapolating it to steel. This does not happen. High-strength steels can suffer cracking due to exposure to strong (stronger than ammonia) caustics, and corrosion in acids can cause hydrogen charging that leads to hydrogen-induced cracking, but ammonia will not cause SCC in steel.

Several years ago I posted pictures of a Sako stainless blow up that occurred on Vancouver Island while using factory ammo...

Stainless steel during production can develop structural flaws. It is of great importance the steel being used for producing barrels and actions be free of these inclusions... they do happen from time to time and manufacturers are responsible.

Well now that is interesting. But your statement about the steel needing to be free of inclusions is not practical.

Stainless barrels and actions are almost always made of 416 alloy, which is a modification of 410 stainless to provide improved machinability. The modification is additions of manganese and sulphur, to intentionally create MnS inclusions. These inclusions form into elongated shapes called stringers. The stringers are brittle and act as chip breakers when the material is machined, so that you don't get the long stringy cuttings that foul the cutting tool, leading to all sorts of vibrations and poor finish.

So the inclusions are intentional and are required to enhance machinability. If you remove them you are just back to 410 stainless. The manufacturers of 416 just have to be careful to not get too many stringers, or stringers that are too large, to avoid weak spot in barrel walls.

Two fun facts: The bursting of AR10 serial 1002 in testing at Aberdeen Proving Grounds in 1956 was caused by a 416 barrel that had excessively wide stringers in it, creating a weak point in the barrel. And, this is why you don't commonly see stainless shotgun barrels. The barrels of a shotgun are so thin, using a machineable grade of stainless the risk of the stringers compromising the barrel would be too high.

 

[Rman]

Apparently, I wasn't clear enough with that comment. What I meant is that it would appear that it is possible to blow up a gun without any barrel obstruction, but is very unlikely.

Not sure if or when we'll get more information about this current incident. It could be a while if we have to wait for some explanation from Sako or Beretta. Given all we've seen here, the faulty stainless steel explanation (such as the existence of sulphur inclusions noted by guntech) seems like the most likely--particularly since it was seen as the cause of similar incidents in 2005.

To be very clear. the incidents noted from 2005, as well as the one that Guntech posted, were due to barrel failure. Specifically fluted barrels. Also of note, is the nature of the failure Guntech posted, as opposed to the nature of the failure posted originally in this thread. They are not even remotely close. One look at bolt lugs, barrel, and action confirm this.
What is the agenda here, exactly?

R.

 

[LordEvilPepper]

Federal ammo strikes again...

The have such ####ty quility control that you get these rounds that cook hot and blow up guns... especially ones with exsisting flaws.

The brass that blew up my GSS wasn't completly buggered, it was just a hole out the side. If that round had been fired in a gun with a structual weekness like this sako... odds are it would have b,own it up too.

 

[South Pender]

To be very clear. the incidents noted from 2005, as well as the one that Guntech posted, were due to barrel failure. Specifically fluted barrels. Also of note, is the nature of the failure Guntech posted, as opposed to the nature of the failure posted originally in this thread. They are not even remotely close. One look at bolt lugs, barrel, and action confirm this.

First, were Sako 75s available with fluted barrels prior to 2005? That seems like a more recent development, but I could be wrong. Second, as noted above, Sako stated:

“The barrels would break up lengthwise into several fragments, and in some cases, other parts of the gun also broke. The problem was attributed to a weakness in the stainless steel used in the manufacture. Guns of the series in question were sold to several countries, from the United States to New Zealand, before the defect was noticed."

So it doesn't seem like much of a stretch to imagine that, if poor stainless steel was used by Sako in these barrels (and note that actions broke as well), the same poor quality stainless could appear again with Sako and be used in the later action of the 85 that blew recently. I'd say that these two sets of incidents are more than "remotely close," but instead are quite close.

Also, it's clear from the pictures guntech posted that more than the barrel failed in that incident. The action came apart as well.

 

[Rman]

There appears to be quite a bit of imagination at work in this thread?
As illustrated in Guntech's photo, the action came apart due to barrel failure, as did the rest of the actions (parts) referenced by Sako themselves.
Again, not sure of the agenda, however, the two failures have very little in common, as referenced by the bolt lugs, action, barrel, and ruptured case. If one knows what they are looking at, and for, as suggested, then it is very obvious that they aren't quite close at all.
The chances of Sako being stung by the same quality control bee previously encountered would be slim to none. If this was the case, they would be more documented failures? The same goes with holding the Federal ammunition at fault.
Nothing is impossible, of course, but the numbers of rounds and actions produced, would certainly show more failures on a far greater scale than one?
So what is it, exactly, that you are after with the assumptions, guesses, and selective reading?

Sako 75 production started in 1996 and continued until 2007. Model 75 Finnlight (fluted barrel) was introduced in 2001

R.

 

[medvedqc]

You definitely cannot chamber a 300 Win in a 338 Win chamber. I think he may be thinking of the time he purposely fired 300 Win Mag ammo in his 375 Ruger as an experiment.

Ted

that is certainly where the confusion is coming from me, were we shot 300 wing ammo in the 375 ruger. sorry for the confusion. thank you Ted. better memory than i lol.

 

[South Pender]

So what is it, exactly, that you are after with the assumptions, guesses, and selective reading?

LOL. It seems pretty obvious what we're all "after" here: to know what caused the blow-up of the recent Sako 85 here in B.C. There's no "agenda" that I can see--other than to get the facts right down to the cause. It seems that you are making many assumptions yourself. First, that the same stainless-steel problem couldn't happen a second time. Of course it could. Would there have to be more "documented failures"? Again your assumption, but not necessarily the case at all. From all I've seen and read, I still feel that metal failure is the most likely cause.

It may take a while to get a more-detailed explanation for this occurrence, and I hope we get that.

 

[Rman]

Take a really good look at the two failures shown in this thread, objectively. You have one example that is known to be caused by a material flaw, while the other is unknown. Try and see what the two really have in common?
The first shown, has detonated into bits, sheared bolt lugs, has an intact barrel, and brass embedded throughout critical parts. These are all signs of a critical overpressure.
The second shown, has a barrel in bits, an action split in half, and is showing us a ruptured case ahead of its base. As the failure here is of a known cause, which is a flawed material used only in the manufacture of the barrel, not the action, we now know what that type of failure can look like.
Yet, somehow, given all of the information provided, you want to extrapolate that it is a flawed material in the action, that has caused the first failure? Sako didn't have issues with action material, only barrel material, and in a previous line of rifles, that stopped production in 2006.
Would there have to be more documented failures? Given the number of actions produced, yes. There are thousands and thousands of them. If there were material flaws, then they would most certainly be exposed, as they were previously. Material is always sourced in batches for mass production. There is no assumption here, only fact.
While you feel, or really want this to be a failure due to material, the chances are very very low that this is the case, given the numbers made, how the material is sourced, and the pictures and information provided.
We all want to know the cause, but are not likely to be told.
It is very difficult to detonate a rifle, period. The case shown, clearly did not cause the damage shown. The lack of information being provided on the other thread certainly isn't helping, as it is secondhand, and not exactly accurate. The vast majority of action failures are indeed caused by an operator error. Cleaning rods left in barrels, a laser sighting device left in the barrel, the wrong ammunition used, the wrong powder, and wrong bullet size, are all some of the more popular, and documented failure causes. In each one of these, the action looked far more like the first shown, and far less like the one shown caused by barrel material flaw.

R.

 

[pathfinder76]

You would have to really try to get a 308 Norma into a 338 chamber. The shoulder is almost a tenth of an inch further ahead.

7mm Rem and 264 Win definitely will work.
Ted

Works great actually. Tested pistol powder charges Saturday. Will form the rest today.

 

[pathfinder76]

LOL. It seems pretty obvious what we're all "after" here: to know what caused the blow-up of the recent Sako 85 here in B.C. There's no "agenda" that I can see--other than to get the facts right down to the cause. It seems that you are making many assumptions yourself. First, that the same stainless-steel problem couldn't happen a second time. Of course it could. Would there have to be more "documented failures"? Again your assumption, but not necessarily the case at all. From all I've seen and read, I still feel that metal failure is the most likely cause.

It may take a while to get a more-detailed explanation for this occurrence, and I hope we get that.

It is certainly hard to ignore the fact that this keeps happening to stainless Sako 85’s. Especially when they aren’t likely the most common rifle at the range.