Just when you think you've heard it all....

I came across a request for detailed drawings for the bolthead of a No4 MkI*. Ok, perhaps not anything unusual there, some collectors are always chasing tech docs of one sort or another.... But, this gent wants to make his own bolthead, and doesn't like the fact that the three boltheads he owns are different sizes. Now, the reason he gives for this is the fact he had a catastrophic failure of a bolthead which resulted in him getting sprayed with burnt powder residue, the shooter beside him being burnt also, and a passing range officer being struck by a piece of the shattered bolt head. Not wanting to allow the thread to deviate into an investigation of the failure, he has said only that he was shooting cast bullets out of handloaded ammunition at the time.... and could find no reason for the failure....

Anyone else hearing alarm bells here? I suggested he put his trust in the proven track record of the Lee Enfield action and parts, but re-visit what he had done wrong that could have caused the misshap...

I did say I wasn't aware of any such failure that couldn't be attributed to operator error in some way... have I made a wrong statement here?

Things that come to my mind from the scant information available so far...
Was it a DP rifle?
Was the bore fouled/ blocked?
Did his handload cause a serious overpressure by
1) a double charge of a fast burning pistol powder popular for lead pill shooters?
2) Or a half full case and a flashover of the powder.
3) Was the projectile sized correct?
4) Not crimped too tight or even too hard compound?

Another though just to mind, is the bolt missing the lug which prevents the cocking piece falling when the bolt isn't locked... allowing ignition and the unlocked bolt flying rearward from the pressure- effectively an out of breech ignition?

...any discussion welcome here... have I missed something? Or should we all be making our own boltheads so we aren't injured at the range?

I have been following this saga elsewhere and find it fascininating. The gentleman claims to be a machinist but does not want to reverse engineer the design by measuring parts he has in hand. He seems to think that the orignal drawings are a holy grail that will solve all his problems. He apparently does not know that the the drawing will be in Enfield Inch measurements where a US inch is not the same as the Enfield Inch. Not a problem for the British as Enfield made their own tools and gauges (which is why the problem existed into the late 1920's). He does not consider how the measured bolt heads can vary so much.

I wonder if this is all a mechanism to allow him to shift blame away from personal responsibility. Boo Boos and hand loaded ammunition go hand in hand.

Had a similar incident here in Nova Scotia a few years back. I drove the RO to the hospital....remarkably quick service when they hear "Firearms malfunction"....

In the end, the determination was that it was likely a flashover of a reduced powder charge in the case due to inattention while reloading.

NS

The thing you almost always find is you NEVER get all the facts about one of these incidents. It was NEVER his fault. There's always"By the way, one more thing" that doesn't seem to surface. This whole thing is undoubtably his error during reloading. Whether he's aware of it or not. If we had ALL the facts(powder, charge, primers used,squib possibility) we'd be able to point to exactly what the problem was before the catastrophic failure of a proven battle rifle. These guys are always a master reloader.

Son - as you'll have seen I also asked him if it was a resurected DP rifle and what load he was using.
John Sukey asked the same Q's.

I thought that guy's story was an exact repeat of one that appeared on that forum a year or so previously - and which appeared to be some sort of troll attempt? I predict that there will be no photos, no independent account, no clarification of the handloads in use....

Hmm, out of all the things that could be deemed remotely feasible in the way of a firearms malfunction I would have thought a bolt head to be so well and squarely supported that disintegrating what is almost solid little lump of steel would be darn near impossible. I'm with son, I want to see pictures.

C'mon you lot, this bloke has the right to commit suicide any way he likes, just a pity it will be another firearm related incident.

Ah, reverse engineering; that's how we did the M-10 bolt and bolthead. The receiver and barrel drawings provided reference surfaces. The trick was to measure a LOT of components to establish a range. We then applied much of the tolerance schedule from the No1 Mk111 bolthead drawing to the No4 data and used that as a starting point before fooling around with the extractor and squeezing in a plunger ejector.

As long as the machine shop, the heat-treaters and the metrology lads do their part, it all works fine.

My two bob's worth is that there was something very odd about that rifle that blew up:

Excessive headspace from bolt and / or receiver wear / mismatch is a good place to start. Fitting a No3 bolthead MAY have closed the gap, but then there was still an ignition issue. So, maybe the rear of the bolthead was "adjusted" to allow greater striker protrusion. This only works up to a point (Boom! Tish!....Tish!....BOOM!!), because, eventually, the "reverse ogive" of the striker will jam solid in the matching bore of the bolthead. Now, were someone to "adjust" the striker or bolthead to allow more clearance, they could achieve greater protrusion: not that this is indeed a good thing.

Note also that the original boltheads were made from case-hardened mild steel. Early SMLE ones were malleable cast iron and later case-hardened mild steel. The term "nalleable" in relation to cast iron is important. What is also important to note is that the No1 Mk111 boltheads were only case-hardened on the face and the "hook" (the elegant bit that rides along the RHS rail). The rest was left "as forged". No4 boltheads were probably subject to similar treatment. The idea is that the "hard bits" will resist wear whilst the relatively "softer" bulk will absorb and transmit firing stress without catastrophic failure.

My experience with No4 cocking pieces has been instructive in that they seem to break much more often than No1 types. All the examples I have seen of fractured No4 types have been UK production. I suspect this is because Britain was actually being bombed whilst trying to produce war materials. Not only that but modern pyrometers and such were nowhere to be found. "Cherry red" is a bit subjective when you are working in different light colour balance and intensity on a 24 hour cycle.

ALL carbon steels "age". The classic sign is an increase in crystal size. Hardened ones tend to get harder and more brittle over a century or so. Ditto "hardened malleable iron" viz. older flint and percussion type toys. "Over-cooked" ones go bad a lot faster. It is interesting to note that Brit ordnance specs for the SMLE basically forbade the use of any "alloy" steels without the submission by the contractor of a quantity of specific sample pieces to be tested before use was approved. They also allowed for "re-heat-treatment" ONCE and only under closely specified conditions and only for certain parts.

Hmmm........I've got a shot out 303/22 barrel and a couple of SMLE actions laying around.

I wonder how a .30 cast pill and a large dose of Trail Boss would go?

I'm backing the bolt head will remain intact

I just bought my first first milsurp Enfield from J and G in Prescott, Arizona. I've been surfing as many sites as I have the time for just looking for general information about these rifles.

I did happen to stumble onto a British forum post that had a similar story. Don't know if it was the same fellow. May have been, since I recall a statement to the effect that he'd posted his search for some drawings on different forums.

Distressing to know that such things as this are possible. Distressing but, not really surprising.

My brother-in-law's neighbor in California suffered such a catastrophe with his newly purchased rifle with store bought ammo. Don't know the particulars. Only that it happens from time to time.

The extent of my knowledge about Enfield rifles includes only the caliber; (303) I don't presume to know any more than that. I've come to the conclusion after reading this guys story that it will be a good idea to let a qualified gunsmith to check my Enfield before I attempt to shoot it.

I must say that after reading the story, -if it was the same story- what I read there and what I'm reading here seem to be somewhat contradictory on some points.

When I was a kid, we used to play a game where we'd have one of us kids whisper something specific into the ear of another chosen kid. Then we'd have that child whisper what he'd heard into the ear of the next kid; and we'd repeat that whispering till we ran out of kids.

Without exception, after about the fourth or fifth kid, the thing that had originally been whispered into the ear of the first kid was completely skewed.I suspect that the same thing has happened to some extent here.

As I recall from reading what I think you're referring to; although your assessments may be spot on, there seem to be some discrepancies in the interpretation.

At any rate, I'll be looking for a competent gunsmith in the next few days. I'll have a better idea now on what to ask this gunsmith to look for.

44magnum

Quote:

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Originally Posted by 44magnum

As I recall from reading what I think you're referring to; although your assessments may be spot on, there seem to be some discrepancies in the interpretation

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Either there was a failure of the bolt or there wasn't...

Old P. O. Ackley was doing evil things like that back in the early 1950s, just to see what happened. You might have to ream the chamber out to accommodate the bigger bullet, however.

On a similar note, I once did an experiment with a M38 Carcano carbine.

I clipped a 7.62 x 39 ball round, complete with steel core and steel jacket, under the extractor of the Carcano bolt.

Lashed the rifle to a car tyre and attached a long string between the trigger and the big tree I intended to hide behind.

Inserted the bolt and let her rip.

Did the rife explode? Nope.

By all theories, the oversized bullet should have occluded the bore and the propellant charge thus blown back through the action. Nope.

The bullet punched some interesting-sized holes in an old washing machine used for a "target" and ended up as tiny shards except for the solid steel core, which was only slightly bent and embedded in a board behind the target.

The bolt opened easily and the case came out slightly less tapered than it had gone in.

I was not game enough to repeat the experiment but the action went on to be incorporated into a 7.62 x 39 single shot (with an appropriately bored and chambered barrel, of course!!), for my kids, .

Folks have allegedly converted 6.5mm Type 38 Arisakas to .308Win by simply boring out the barrel a bit until a reamer is accepted, but I have never seen one in the flesh. I have seen and fired Arisaka Type 99 rifles sleeved and re chambered for .303 Brit, but the bore size is essentially the same.

One should be careful when experimenting with devices that run at over 50 thousand PSI in front of your face.

And another thing.........

Cast bullets.

What alloy?
What hardness?
What barrel condition?
How many rounds?
What propellant and loading?

The problem with cast bullets in any serious centrefire is that they have to be as hard as Hell and gas-checked to achieve anything like decent velocity.

If you do manage to get that right, things are sort-of OK unless you stuff up the propellant. Too quick and it can get exciting.

Furthermore, cast bullets are an issue in fast rifling twists like the 1: 10" in the .303. Crank up the velocity, even with good alloy and lube, and the things will just smear their way down the barrel leaving a LOT of metal in the grooves.

This will of course, rapidly build up as it helps strip more metal from each subsequent bullet, gas check or no.

The accuracy will go completely out the window very quickly. Some folk have been tempted to "clean out" this metallic crud by whacking a jacketed bullet up there to "scrape it out". EPIC FAIL.

All that happens is that he accelerating jacketed bullet bulldozes the soft alloy towards the muzzle until the barrel can no longer handle the strain.

What results is a nasty "ring" where the jacketed bullet pushes past the accumulated soft alloy from the cast bullets. Exit one barrel.

DO NOT mix jacketed and cast bullets in any serious centrefire rifle.

Gee i dont know most of the catastrophic incidents ive ever seen on ranges have either been to the firer haveing handloaded there own ammo and not having a smick about what they are doing, IE: a gentleman at the range fires his rifle with subsequent fire and brimstone from the breech, with the projectile keyholing through the target. Question what just happened and why did it do that.
Well that was a mauser action with powder tamped down into the round, to say it was slightly overloaded was understated.
Numerous sporting actions and military ones i have seen when the firer has not understood what they are doing when reloading ammo.
As to factory produced ammo well some of that is running hot loads to a point where the primer is flattened but rarely does it cause a malfunction.
All other malfunctions i have ever seen are do to either overloading to unbealevable ammounts which then causes the failure, or a failure of the ammunition IE split case missing primer after ignition etc.
So by the sound of it, it sounds like operator error to me!!
Regards
Fergs:yikes:

Once again , we get back to the issue of rifles being built around the ammo, not vice versa.

Let’s take a couple of examples.Some years ago I had the misfortune to witness someone nearly destroy a SIG AMT on a range. The AMT is basically a “civilian export” version of the fabulous Swiss PE-57.but in 7.62 NATO.

The well-heeled owner of this fine piece of machinery had decided to shoot it using “bargain” steel-cased, copper-washed ammo; Bulgarian, I believe. Now, this ammo performed quite well, accuracy wise, in bolt action rifles. Primers seemed to be somewhat more corrosive than in real NATO spec, but that was not insurmountable.

The AMT in question ended up with the breech lock assembly jammed partly to the rear and the bulged case still attached to the bolt-head; this making disassembly a bit tricky. It was eventually cleared and revived, but it was a close call. Oddly enough, the same ammo had been used by other shooters in H&K 91 s without apparent dramas. I understand that this practice ceased forthwith.

I used to own both types of rifles and NEVER used anything but brass cases in them. The simple reason is that both systems were designed around BRASS-cased ammo. The mechanical properties of the correct case material are inextricably linked to the way these delayed blowback mechanisms work. The weird thing is that the SIG and the H&K have utterly different felt recoil. The H&K “jabs” whereas the SIG “rolls”. The SIG can be fired all day with standard ball without the shooter ending up punch-drunk.

A completely different problem afflicted a Portuguese pattern AR-10 on another occasion. I was acting as a safety officer on the line and noticed an “interesting” firing report associated with unusual flashes from odd parts of the rifle.

Remember that this was a REAL mil-spec, Dutch-built AR-10.The magazine was blown out, the upper and lower receiver were bulged and the bolt was partially withdrawn from the barrel extension. When we got the thing apart, the brass case was a mess. The primer pocket was elliptical and about twice as big as a normal one. The primer appeared to have evaporated. The clue was at the other end of the case, however.

The neck was strangely thin, tapered and ragged at the front. “AH, Ha, an untrimmed reload”.

It seems that this chap had never read the “other” stuff in his reloading manual. Necks that are too long simply get swaged down and into the bullet itself during chambering. Thus the bullet is retained by much greater force than normal and when it goes “bang”, it REALLY goes bang.

ALL the information in the loading manual matters.

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Originally Posted by Bruce_in_Oz

ALL the information in the loading manual matters.

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I always shake my head when someone asks me "how do you reload...". I say buy the Speer Manual, which is the best one I've come across, read it, then read it again, and then we'll discuss it. Plenty of experienced reloader NEVER measure case length.