Post mortum LE bolt failure...

[jmoore]

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."

[303Guy]

More information on this; the primer did not rupture according to the shooter. He says the cases were all fine.

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.

He did say that after the fist full power load there seemed to be something wrong but he couldn't see anything.

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?

First impression? A sham.

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.

[PrinzEugen]

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.

[tbonesmith]

I think we should leave this thread here.

[browningautorifle]

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...

[303Guy]

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.

[browningautorifle]

Two major causes for pierced primers are high pressure and excessive firing pin protrusion...any others?

[Peter Laidler]

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

[oldpaul]

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

[Ridolpho]

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