Any ideas what happened here?
Attachment 46152Attachment 46153
I can understand a failure on the lugs or before, but after?
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Any ideas what happened here?
Attachment 46152Attachment 46153
I can understand a failure on the lugs or before, but after?
Failure has occurred around the bearing surfaces of the lugs.
Is it a result of poor heat treatment during the hardening process of the lugs, or is it just a result of crystalization of the metail over time?
Could also be from poor bolt fit. If only one lug was bearing the load then the bolt will be strained in this area.
I have no suggestions but being curious I would like to know. Did that break firing a normal round? Milsurp or sporting?
May I keep copies of your pics for my own interest?
Hi, not my pics, someone elses, Im asking the "pros" in here for ideas why. It looks after the lugs in an area I'd expect to be stress free, so Im wondering what happened.
"Prepared it for firing and put some light hand loads through. Stoked with the results I decided to test it against some factory ammo. First round gave a hell of a whack, sticky bolt but no hard extraction or real issues. Thought to myself they must have overcharged that one. Chambered the next something didn't feel right. Had a good soldiers 5 and nothing I could see wrong. Had a shot, crack, safety glasses smashed, bloody sore head and a shattered bolt. It snapped just forward of the bolt handle and sent **** flying everywhere. I've got a few garks on my trigger hand and forearm on the other. By my account I'm lucky to have walked away from that. "
is the decription...
Wow. Well, I speculate that it would seem like a blown primer driving the striker back with enough force to break off the bolt at the stress point. I had a look at my SMLE bolt heads and although there is a vent hole in them the vent hole is largely covered buy the receiver side wall. The shooter didn't say anything about the primers but he did mention the first full power round being 'hot' (then he carried on firing the others!) It's easy to criticize someone after the fact, I know, but he should have stopped right there.
Anyway, I'm waiting for the guru's to come in to tell us what they think.
Those magic words... "hand loads"...
The whole firing description sounds like massive over-pressure in the rifle.
---------- Post added at 09:23 AM ---------- Previous post was at 09:20 AM ----------
Quote:
Originally Posted by 303Guy
Blown primers have very little effect. Sometimes one has enough pressure to put the striker on half-cock, but they usually just blow oil and soot back out around the firing pin and into the shooters face. The pressure levels are insignificant compared to the structural strength of the rifle.
Yeah im kind of going huh? I still dont fathom why it broke so far back, did it bend due to bad lugs and snap? From what I read he said it was factory ammo...
High quality/definition photo of the break, cleaned with methylated spirit first would very probably tell the metallurgists here, such as JM and Breaky exactly what caused the fracture but I suspect TBox has it in one! He's certainly on the nail re blown primers. There used to be lots of them with 50's made factory blank for some reason and it'd just foul up the insides of the bolt and occasionally cause a half cock
Comments for what they are worth as we don't have the parts in hand.
1. Steel does not crystalize with age. Steel as it cools forms crystals with noticeable, under the microscope, boundaries separating the big crystals. Variations in boundary physical and chemical properties can affect material performance.
2, I agree that the culprit was handloading. I am not a handloader and do not intend to. From what I have read, reduced handloads can be very dangerous. SARCO's office manager Glenn DeGrooter was killed by his using reduced loads in a Winchester Lee Navy rifle. It was explained to me that there is a balance point of powder vs. available oxygen in the cartridge case. Less powder in the case and more air caused a "double detonation" which increased chamber pressures. A crack was started and full loads finished the lot off. Perhaps more knowledgeable people can expand on this.
And don't forget that in Post #4 the fellow shooting the rifle said "Thought to myself they must have overcharged that one." Of course there he was talking about the factory ammo. It would seem that the problem came from one of the reloads he fired before.....Quote:
Originally Posted by Thunderbox
Remember some of this factory ammo has been around since before our time. Some of it has been cooked in various deserts and storage facilities for years and then purchased by gun dealers for sale in another area. This ammo is well known for it's unreliability. It can create a bomb waiting for detonation...maybe it was the light loads, but I'd suspect the wheel was spun and the cooked surplus factory round came up. I doubt the OP or the rifle owner can even tell us reliably what the cartridge was...guess work...he'll likely not sort this out for sure.
Based on the very limited info it doesn't appear that either the bolt locking lugs or the shoulders in the receiver failed yet the quote from the shooter indicates the separated rear portion of the bolt flew back with some velocity! A simple stress concentration and associated crack near the lugs (due to heavy overpressuing) couldn't cause that, could it? Something had to drive that separated portion rearwards. But if blown primers, at worst, can only set things back to the half-bent, then what could do it?
Ridolpho
Maybe the "light loads" succeeding in plugging the barrel with a few bullets.
The first factory load then creates a massive over-pressure. Possibly the front part of the bolt has been blown out of battery with the chamber, and in doing so has pivoted around the bearing faces at the locking lugs. The back part of the bolt is then being pressed against the unyielding base of the boltway - thus bending and fracturing the bolt body at the pivot point.
I bet there is the whole story to be deduced, if photos of the bolt & cartridge cases were to be posted...
But I'll bet a pound to a slice of xxxx that even with this catastrophic (?) failure, the bolt didn't lift and open.
Actually, in mechanical engineering investigative terms, it wasn't a true catastrophic failure eitherwas it. It held firm. Just a point to ponder!
That would do it...Quote:
Originally Posted by Thunderbox
if he shot an under pressured round and/or a did not seat the bullet right with the hand loads and plugged the barrel then fired another round i would expect a lot more serious failure. like a blown up chamber.
Quote:
Originally Posted by mrbungle
IIRC no-one has ever reported such a thing; maybe the chamber and receiver ring are the least likely to fail as they have the greatest structural strength?
Maybe someone else remembers a Canadian (?) website where they described a destruction test of an SMLE? They had a barrelled action, where the action had already been "weakened" by having been drilled through the wall multiple times for scope mounts. They ran an experiment to try and cause the rifle to blow up by blocking the barrel. IIRC, mud, snow and other "service use" bore obstructions had no effect whatsoever.
They then tried hammering some bullets into the bore, but these got blown out, leaving some bore bulges. Finally they started hammering metal spikes into the muzzle. Apparently, on each firing, the section of barrel containing the spike fractured and came off, leaving the remainder and the action still serviceable. IIRC they finished the rifle off by using a spike in the bore and some cartridges filled with Bullseye or some pistol powder. Finally, the receiver gave way in the usual SMLE fashion - bending and distorting so that the bolt could not be cycled. They could not cause a catastrophic event, and the chamber section of the barrel remained intact.
In some cases yes, but thats when your using a reduced rifle powder charge, I,ve been downloading for some time but use fast burning pistol powders, I,ve experimented with over charging and under charging the case, (all done under controlled conditions) with me standing a great distance away.Quote:
Originally Posted by breakeyp
I suspect one of the light loads was too light, and may of left a bullet in the barrel, TB mentions the SMLE and blocking the muzzle end to try and blow the rifle, I would think the chamber end blockage may of been at fault... a common problem with handloading is a lack of charge in the case, the primer will push the bullet so far.... cant remember how far, as I havent done that for many years.
Quote:
Originally Posted by browningautorifle
No doubt about it Jim, you could be correct. But we will never know, he could have been talking about current production civilian ammo like that sold by Remington and several others, fresh from the factory.
Firstly I'm NOT "more knowledgeable" on this subject but this is my understanding.Quote:
Originally Posted by breakeyp
A case with plenty of powder will cover the primer so when detonated the "front" of the resultant explosion will travel forward building pressure & so pushing the projectile forward & out the end of the barrel, a case with too little powder will leave the primer exposed & when detonated will/can cause the powder to be ignited at multiple points due to the flash over from the primer, this not only causes virtually all the powder to ignite simultaneously but also multiply "fronts" traveling in different directions which collide causing major pressure spikes.
Hi,
Ive seen the result of a barrel blocked with ice...the guy was walking along and put the muzzle through snow, it froze in and when he fired it peeled like banana, the chamber though held....it is a lot thicker after all. Ive seen a few bulges and breakes as well, all after the reinforce Im all eyes if someone shows me a chamber failure...!
Im going with a bad hand load as well, Im currenty loading 39.5gr for 174 and 37.5 for 150gr and the max listed is about 43 for adi 2208, how you get much more in I dont know the case looks pretty full at 39.5. Ive asked for more pics incl cases....and if the serial numbers matched. One thing Ive noticed with kiwis that gives me the sh**s is their "it will be alright attitude" and let buyer beware....I'll also ask what powder he used....he says he checked the barrel was clear btw.
The reason I suggested a blown primer is that I have recently read a report of a cocking piece being driven into a shooters eye caused by a blown primer. I recall he lost his eye! (Must double check that. Was that on this forum?)
Another one;5thBatt, the reduced charge detonation is called SEE for secondary event explosion. The description of events is that there is insufficient powder to build up pressure and while it ignites OK as the bullets moves forward it increases volume which reduces pressure to the point where combustions slows down and the bullet stops. The powder is still burning and now builds pressure very rapidly behind the now stationary bullet which can't accelerates away fast enough and the powder explodes.Quote:
... a .303 primer and had the No4 Enfield reset to full cock----after it blew ...
Only some powders are prone to this under certain conditions. AR2208 (Varget) is not one of them. The worst one can do to overload a 303 with AR2208 is create a 308 load which has a compressed charge at max load. Other powders are different.
A reload with no powder can leave the bullet in the throat and with the slam loading of the cock on closing can push the bullet of the fresh cartridge back into the case doing three things; reducing powder volume an doubling the bullet weight plus misaligning the second bullet! . I use a case filling powder to prevent the bullet from being pushed back. I also have a routine of standing all cases upright in a reloading block and shining a light down each case to inspect the powder charge - no exception! I never powder then bullet a case.
With this rifle the report says the shooter noted one heavy load with the full power loads and the last shot blew the cocking piece into his glasses shattering them.
Consider that the area behind the lugs are being stressed by the stress concentration at the junction of lug and bolt body (there is an illustration of these stresses out there - if I can find it I'll post the link) during firing so a severe blow could fracture the bolt at that point rather than further back. It sounds like something was damaged on the first shot. The second shot blew more than the bolt rear off - the shooter got stuff in his shooting hand and left forearm. That second shot was over pressure and the case ruptured! There was no bullet left in the throat.Quote:
"Prepared it for firing and put some light hand loads through. Stoked with the results I decided to test it against some factory ammo. First round gave a hell of a whack, sticky bolt but no hard extraction or real issues. Thought to myself they must have overcharged that one. Chambered the next something didn't feel right. Had a good soldiers 5 and nothing I could see wrong. Had a shot, crack, safety glasses smashed, bloody sore head and a shattered bolt. It snapped just forward of the bolt handle and sent **** flying everywhere. I've got a few garks on my trigger hand and forearm on the other. By my account I'm lucky to have walked away from that. "
here is a chamber failure. not a enfield but a M-14 , the whole damn thing exploded... with split chamber.
http://www.thegunzone.com/m1akb.html
Fasinating report on it as well....good indicator not to use a no name barrel....Quote:
Originally Posted by mrbungle
http://www.thegunzone.com/m1akb/762r.html
Quote:
Originally Posted by 303Guy
I think we all agreed that story was probably rubbish. If you think about it, primer gases blowing back into the bolt would act on the face of the firing pin - driving the firing pin back. I don't think anyone's heard of a primer doing more than half-cock - because the primer lacks the energy to compress the firing pin spring any further. If a primer were to compress the spring further, then it would simply come to a point where the spring is solid (i.e. not much past full cock). The primer gas would then have to have enough energy to shatter the end of the bolt body, so that the striker, pin and spring can carry on going backwards to get anywhere near a shooter's eye. I don't think that has even happened when someone has fired a rifle with no bolthead fitted, and the main propellant charge is free to exit rearwards.
You have to be wary of stories about shooters being injured whilst firing Enfields. Mostly they seem to be urban myth. I'm not aware of a any that have been proven, let alone with a standard rifle firing standard ammunition.
I've had lots of blown primers with questionable ammo in Lee Enfield's of various types. I've never had any action as result, none at all.
Comment on the "light" load used,
"The load is based on Ed Harris' "the load", which is 13gn of Red Dot. I put a .311 sized GC165gn hard cast pill on 13gn of AS30N primed in CCI #200 primed cases trimmed to 2.22. "
ho hum....
Alliant Powder - Reloader's Guide
Red Dot a cowboy (LOL) pistol load.........
Ed Harris articles for reduced loads in Reloading and Ammunition Forum
Never the less, a braver man than I.
It's not the primer gasses, it's the main charge gasses and those would act on the firing pin collar.Quote:
... primer gases blowing back into the bolt would act on the face of the firing pin - driving the firing pin back.
I might be referring to the same event ssj is talking about in which case his eye was not damaged. I'm looking for that post so I can get my facts right.
And the No4 has a working gas vent in the bolthead! So here we have more than the half-cock that is said to have been observed by our members here.Quote:
Pierced a .303 primer and had the No4 Enfield reset to full cock----after it blew past full cock and raked the sear bent over my thumb.
The story I mentioned might be urban myth but here we have photo's of a broken bolt with a report that the rear piece struck the shooter in the face. That rear piece is reasonably heavy so the forces involved are considerable. The shooter said it hurt his face.He also said he had injuries to his right hand and left forearm so there was a blowout.Quote:
... bloody sore head ...
Quote:
I've got a few garks on my trigger hand and forearm on the other.
Quote:
Originally Posted by ssj
I very much doubt this the above was the cause , I think what we have here is maybe a mistake regarding the original story, I,m thinking it may of been commercial ammo first then the handloads, I would think he went over the required charge, this could or may have give the stated affects.... and maybe the wet feeling in ones pants.
Regarding my own downloads, the proof is in the pudding they say, click on the link below have a look at the target in the pic,
L42 repro at the range
On this reduced load thing - many people use pistol and shotgun powders for cast bullet loads because they burn well at low pressures and it's much cheaper. Looking down into the mouth of a rifle case, the difference in hight between 13gr and 26gr of Red dot is negligible. But 26gr (a double load) is over the top.
I always advice against fast powders, suggesting a medium to slow powder that will not be an overload even with a full case. That too can be risky if too little of a too slow powder is loaded (S.E.E.) Pressures will then be low enough and velocity not too high (accuracy goes south with cast if pressure and velocity is too high). There is another powder that can be used in a rifle case for subsonic velocities with about the same burn speed as Red dot and that is Trail Boss. It's bulky stuff and fills the case! Unfortunately it is too fast so is useful only for light loads.
First impression? A sham. Without more and better detailed photos that's about all I got. Not even going to link this thread to the "Gallery of Dramas."
More information on this; the primer did not rupture according to the shooter. He says the cases were all fine.
He did say that after the fist full power load there seemed to be something wrong but he couldn't see anything.Quote:
I checked the cases and they were fine. I checked them against a square too and they looked to be straight. The only thing I noted other than the bolt was the firing pin had snapped.
With no gas pressure acting within the bolt it becomes kinda hard to imaging what could have thrown the bolt back with enough force to break his glasses. He didn't actually say the broken bolt shot out of the action, only that it hit him in the face. " and sent sh*t flying everywhere." Did it simply shatter at the fracture under load?
Actually, after reading this fellows whole thread, he seems to me to be quite genuine. He did not start out with a dramatic display of photo's and claims. He only posted photo's after being requested.Quote:
First impression? A sham.
Strong words from jmoore - and he'd only say something like that if he really thought it, as one of our most knowledgeable and level headed members.
Personally I've been watching a glut of metal obsessed postings on milsurps of late with something of a feeling of deja-vu, wondering if some of our old friends have returned again.
I think we should leave this thread here.
I watch these type of threads develop time and again with a common core. We have no idea of what actually happened. Here we sit raving about this or that is the cause, but you seldom get the facts about it in the start. One missing fact is enough. In the army I saw weapon failure take place on occasion and even knowing what the first hand facts were, the true story didn't always come out. Of course, the end findings would be right out to lunch...
I think this failure doesn't even matter. We weren't there and shouldn't argue about something we can't determine...scrap'er out and carry on. I must agree with PrinzEugen, it does sometimes seem a bit trollish when you see some of these threads...
Fair enough then, I'll make this my closing post.
For me this thread has been educational. I've found several witnesses to this kind of event - the broken bolt being the odd one out, from the cocking piece kicking back to cock a rifle to actually been blown out the back of the bolt (not confined to Lee Enfields). Twice with one person with a 1903 Springfield. The first struck his brother on the cheek with force, missing the eye, the second shot through his sleeve into the brush (fired from the hip), both instances with pierced primers.
What I need to know now is what causes pieced primers in the first place.
Thanks all for making this an interesting thread.
Two major causes for pierced primers are high pressure and excessive firing pin protrusion...any others?
Thestriker being blown out oif the back of the bolt............... Are you SURE about this 303Guy? My schoolboy physics and the basic principles of Boyles law......... Or hasn't Boyles law of gas and so forth reached there yet? Striker blown out of the back of the bolt indeed!
I'm sure T/box will have something to add to this absloute load of, er........, Someone remind me of the words that I'm looking for please
Basically, Boyle's law describes a set amount of gas at a set temperature. If the volume available is doubled, the pressure is cut in half. If the volume is cut in half , the pressure is doubled. As a Respiratory Therapist I deal wit the various gas/flow laws on a daily basis. I'm not sure how Boyle's law applies here but I cannot see how a pierced primer could possibly blow a striker out of the rear of a bolt either. Regards. Tom
With apologies to the Moderator for helping to keep this going, I'm curious- does a pierced primer not potentially allow for direct communication with the very high pressure volume within the bore? Flow into the bolt head would be controlled by the very small perforation in the primer (orifice or choke) but consider the energy obtained by tapping off gas well down the bore in actions like the SVT or G/K43. The G/K43's, in particular suffer from severe pounding in the bolt/ carrier. I believe I see gas vent holes in both No.1 and No.4 bolt-heads so is the main consideration here that these are large enough to deal with any conceivable flow into the bolt from whatever? It's not like this issue wouldn't have occured to the designers!
Ridolpho
You got me there!:dunno: I have no reason to disbelieve the fellow but no, I am not absolutely sure. He does present as a straight talking guy. I'll keep looking for verifiable evidence. Anyway, he said the striker shaft broke off behind the collar. I asked and he didn't answer so I don't feel free to quote him.
By the way, it is comforting that you armourers have not heard or seen this sort of thing before. My first thoughts when I hear about this sort of thing are, "oh heck, could this happen to me?"
But here's a thought; if a primer ruptures at 48,000 CUP, the force acting on the striker could be as high as half a ton (as unlikely as that may be). Thinking about it, if high pressure builds up inside the bolt, the striker could be driven back quite fast providing a hammer effect when it reaches the end of it's travel. And we all know what shock loads can do to hard steel. Ever had a chisel fracture and drive a shard into your ribs? I haven't, thankfully but know of a few instances.
You are right OldPaul - so far as it goes, but I am considering the theory in this instance whereby it is alleged that the volume/pressure of gas that could vent back through the two fire holes of the main 'explosive' chamber of the cartridge, back into the primer chamber and THEN back through the pierced primer cap into the bolt and....... and....... When we already know that the vol. of gas generated by the primer might cause a re-cock. But we're talking about a volume of gas that drives the striker rearwards out of the bolt and all that that entails.
Look 303Guy, this ain't not going to happen, believe me!
Don't know why i bother replying to these threads as i just collect the bloody things but (& most probably a stupid question but please humor me) if there was enough pressure forced back under normal firing conditions that could violently force a cocking piece backwards though a pierced primer would you not expect a percussion cap to be blown off & hammer thrown back (or does this actually happen) every time you fired the likes of a old percussion Enfield??
If we didnt reply I think it would be a boring forum....Quote:
Originally Posted by 5thBatt
The best thing about this forum is the level of factual information about the specific firearms we discuss, collect and use. The problem with threads like this is the level of speculation and opinion that may be half correct, unclear or untrue.
I don't want to see too much unsubstantiated opinion, or vague descriptions of circumstances that may confuse facts or confuse newcomers.
By all means discuss what you want, but this is getting pointless, and I will close it soon if it continues like this.
Cheers
Tom
I live in the area where the famous Glenn D. blow up occured. One should not speak ill of the dead, but he made a number of very basic mistakes. That lead to his death.
The most significant was the use of modified cases (from 6.5 carcano), where he had removed material from the head of the case, use of pistol powders with heavy bullets in a case hardened receiver.