Forgive me if I was asleep during one of you classes Mr. Laidler but did any of the 7.62 receivers on the No.4 Enfield up through the L42 7.62 get any special or different heat treating methods than a standard grade .303 No.4 Enfield receiver did.
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Forgive me if I was asleep during one of you classes Mr. Laidler but did any of the 7.62 receivers on the No.4 Enfield up through the L42 7.62 get any special or different heat treating methods than a standard grade .303 No.4 Enfield receiver did.
Short answer Ed is NO! There was no need. BUT, many of the old and tired No4T's passed(?) the 19T proof but were failed subsequently because the bolts were difficult to lift/open. This showed that while they 'passed' proof (?) the extra loading had proved too much for the sometimes marginal hardening of the locking surfaces.
I never quite fathomed out why the bolt would prove difficult to open in these such cases. Any ideas Ed?
Better just clarify that. Subsequently failed proof was as a result of the difficulty in raising the bolt lever immediately after proof and not subsequently, as in after years in service
Mr. Laidler, you have me puzzled now. I would expect the bolt to lift hard or very hard after firing a proof round. The yield strength of the most common cartridge brass is about 60,000 psi +/-. I would think that the brass would flow load the bolt a great deal making it hard to lift. The tester did not use the lug set back measurement method ?
On the .303 Enfield’s two proof rounds were fired, one dry cartridge to proof test the barrel and one oiled cartridge to seat the locking lugs and bolt head. The oiled proof cartridge exerts twice the force on the bolt face, bolt head mating surfaces and locking lug contact area on the receiver than a dry proof or normal cartridge.
After proof testing the .303 Enfield was checked with a .067 head space gauge and if the bolt closed on this gauge the rifle failed proof testing due to excessive bolt set back.
If a three year old hit you in the jaw you would be able to tell the three year old that they was being bad, if George Forman hit you on the jaw and after you picked yourself off the floor you would have a hard time just moving your jaw let alone talking.
To the best of my knowledge NO American commercial firearms manufacture uses oiled proof rounds to test their firearms due to the severity of this type of testing. This to me speaks very highly of the British system of testing their Enfield rifles before handing it to a British soldier to use in combat.
The problem is sometimes the Enfield rifle didn’t like getting hit by George Forman and the bolt was hard to open.
I was going to say Bah Humbug about Enfield inherent weakness and to never fire ammunition that has been oiled or greased but I don’t want to anger Badger and the moderators again and be hit on the jaw and then severely chastised. :surrender:
I think that Ed has answered my querie with as good an example as we'll get. It seems as though that while the barrel and bolt passed proof and the body APPEARED to have passed proof, the new re-proof load was too great for the hardened bolt locking surfaces within the body. As a result, the rifle was withdrawn, stripped and scrapped.
We have already had some superb pictures of the induction hardening spots on the No4 body so from the comments above, if the bolt lugs had recessed the now not-so hard- surfaces, that would answer why it was difficult to lift.
There were also problems in-service with hard extraction in the L42 too. But more about this later......
As some of you know I would never think of beating a dead horse :rolleyes: but with what Mr. Laidler has stated above I hope you see the reason for never shooting oiled cartridges.
You would be more than doubling the wear and tear on your Enfield’s locking lug recesses for NO good reason.
JBS
Below is a link to Varmint Al’s web page, you can find the different grades of brass and the effects of case-chamber friction and bolt stress.
Rifle Chamber Finish & Friction Effects on Bolt Load and Case Head Thinning Calculations done with LS-DYNA
I asked this heat treating question for a very good reason, I wanted to find out how many forum members here find it entertaining and fascinating to read or gather boring technical facts in obscure manuals that has nothing to do with collecting Enfield rifles.
(But it does have something to do with the care and feeding of the Enfield’s you collect) ;)
Thanks, I know of Varmint Al’s. I also have a understanding and knowledge of bolt thrust. Back in the old days when I would catch my guys cleaning or wiping down ammo with oil or LSA I would give them some time on KP or policing the PF to consider the error of their ways. Thanks to both of you for the info on British proofing.
Thanks Ed ... :thup:Quote:
Originally Posted by Edward Horton
Good to see we're slowly making progress ... :cheers:
Regards,
Badger
Thanks Badger, I’m taking a weeks vacation in Canada next spring and I’m going to try hard not to be deported, I may even drop by and see you. :yikes:Quote:
Originally Posted by Badger
(Make sure all you Canadians lock up your Enfield’s) :D
You're safe Ed, we don't even deport Al-Qaeda here. We give them free universal health care, a monthly welfare check and try not to offend their sensitivities in our left wing propaganda newspapers. ;)Quote:
Originally Posted by Edward Horton
Anyway, let's NOT get started on politics here, but if you're up this way, I'll gather up a few local members and you're welcome to drop over for a BBQ. :beerchug:
I've been trying to get Brian and Peter to come over and stay for a visit, so we could make an Enfield party of it, pawing over the wife's collection... :lol:
Regards,
Badger (Doug)
Be careful Badger if you invite Mr. Laidler over here, I just found out last night on the History Channel why the British drive on the left hand side of the road.
It goes back in history to the times of armed British Knights who were predominantly right handed. Riding on the left hand side of the road left the Knights right hand free to swing his sword at on coming traffic.
But what the heck we all know Mr. Laidler is a “cut” above the rest of us Enfield owners anyway. ;)
Earlier when speaking of DP rifles with warped action bodies you said those may have been the result of the rifles being used as a step up when scaling walls in training. That method of helping guys over a wall goes back to the days of the halberd at least. M16 rifles sometimes broke at the hinge when this was tried.Quote:
Originally Posted by Peter Laidler
Anyway I wonder if those rifles had been DP'ed because the bolts already binded in the body, due to either failing a re proof or use of MkVIIIZ ammunition or degraded MkVII ammunition.
Greener's book on "the Gun and its Development" tells of early Enfields suffering Jugged Chambers (not the words he used) preventing extraction. Other works on the Enfields of the pre WW1 era also mention excessive pressures damaging both Enfields and Sporting rifles when Cordite was used in tropical heat.
So far I haven't seen any Enfield bolts that were visibly warped but I did run across one Indian SMLE that had barely discernable ripples down the bolt body. These could be felt when cycling the action slowly and as the tarnish wore they became visible.
I'd like to hear more on those L42 rifles that suffered damage in service.
As for cartridge brass the alloys used for proof test cartridge cases can withstand much higher pressures than common cartridge brass, some US military proof test loads used in destruction testing of new designs (such as when the Garand was first being tested) went up to 120,000 CUP.
Whenever a metal object is mass produced on the scale of WW2 weaponry there will be slight variations in the strength of individual specimens.
Authoritative works on the Enfield written during its development put the figure of 20 tons cartridge operating pressures as the danger zone for the design.
The No.4 should be stronger than the earlier No.1 but how much stronger?
Apparently some destruction testing went up to thirty tons, but I don't think anyone considered this a indication of the ultimate strength of every rifle produced.
breaking strength of the receiver is quoted as 85,000 PSI, but whether this was arrived at by firing a overload or by hydraulic piston is not clear. This seems to be the maximum pressure the action body itself could withstand without breaking in half, or suffering other irrepairable damage.
Whenever a receiver of any sort is re barreled its original proof testing is no indication of whether or not the rifles has been subjected to even higher pressures at some point in its career through obstructions or defective ammunition. Replacement of bolt heads and bolt bodies to put the rifle back into trim might leave the gun appearing fine but with hiden problems, especially since bolt heads were swapped out between rifles and used bolt heads remained in inventory. No way of knowing whether or not the rifle a used bolt head came from was trashed by a overload, perhaps compromising the bolt head.
A final question for Mr Laidler.
Was there a specific type of cartridge aproved for use in the L42 rifles and were there ammunition types prohibited for use in these rifles?
The left hand side of the road was predominantly used throughout Europe and was prohibited first by Napoleon. I believe Sweden was the last country on the Continent to change over to the right. A large number of countries still drive on the left. Not only the pink cloured ones across the globe, but also Japan. A number of studies have shown that driving on the left is actually safer, due to a majority being right handed, thus able to hold onto the steering wheel with the right hand while changing gear. Driving on the right is as ignorant, otiose, abhorrent, useless and decrepit as kms,mms, litres, kilos and decimal currency. Fit only for the mentally obese.:bash:Quote:
Originally Posted by Edward Horton
Villiers
Our country the United States is much younger than the European countries and thus more modern and efficient. The person here in the U.S. sitting in the right front seat has the “shotgun position” and is able to keep both hands on his weapon and engage more oncoming traffic than you would with one hand and a sword.
(It also doesn’t matter here if your shotgun becomes old and dull)
The back seat of the car is common to both continents in that we both have tail gunners for people who ride too close or tail gate.
We can also here in the U.S. give our turn signals and obscene hand gestures left handed which can be seen outside the car and you Europeans can’t give someone the finger if you’re holding a sword in your right hand.
It all boils down to the priorities on both continents, shooting, cutting and slashing or if all else fails hand gestures.
The Canadians are much more peaceful than Americans, the Canadians just sit around drinking beer and watch Hockey players kill each other.
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Is your sword old and dull or is it highly polished from frequent handling....
I LOVE reading boring technical facts- I made a four year degree into eight by poking my nose into obscure manuals and books (which, unfortunately weren't related to actual course work!).:rolleyes: Well, that and working in the firearms trade to pay for school and...Quote:
Originally Posted by Edward Horton
Quote:
Originally Posted by jmoore
The technical details are what I'm most interested in.
The bolt heads used for the 7.62 conversions seem to have been purpose made , and should benefit from the more advanced metalurgy available at the time.
Some older rifles may not have had the best metalurgy, though no doubt the best available at the time, while those rifles constructed in India between 1950 and 1965 are known to have used a alloy that did not stand up well to the oiled proof rounds, the alloy being replaced in later production.
Also since much of the available milsurp .303 and 7.62 ammo may not have been stored under optimum conditions the details of damage to rifles from heat damaged propellants should be of interest to modern day shooters.
Its not uncommon to see collectors telling of shooting .303 ammo manufactured as early as the 1920's, so besides the more common problems associated with old ammo theres the fact that ammo that old did not benefit from advances in production techniques of later years.
Ammo produced in the 1920's for example is associated with the Stress Corrosion Cracking of case necks and other problems, though this seems to have been confined to India, a result of ammonia vapors in the air during the monsoon season. There same effect was noted with ammo stored in stables along with cavalry gear.
I've run across 7.62 Nato ammo so degraded it was scary. Pinholes and cracks in cases and gilding metal flaking away from the steel jacket.
When the powder was put in a steel powder can it dissolved the can into a pile of red dust, and vapors rusted and deeply pitted every steel object near it though these had been well oiled.
According to literature of the pre WW1 period charges of ammo intended for use in India and Africa were reduced, due to excessive pressures when ammo was stored for long periods in hot climates. These days the temperatures here in the Southern US can rival those of early 20th Century Africa. Temperatures in a car trunk can reach 180 degrees after a few hours in the sun even on mild days, and about that high in the passenger compartment if the windows are rolled up.
RAF tests on ammo cases in the Indian Northwestern Fronteir revealed that they could reach temperatures of 160 degrees if exposed to direct sunlight.
Theres just no way of knowing what abuse ammo has been subjected to before being declared surplus. If it was still good ammo they'd use it up in training, or in the case of Canada they'd issue it to the Rangers.
Besides the safety aspects, you'll find that details of manufacture are of great interest to collectors of everything from Hummel Figurines to Singer Sewing Machines.
Phew........ Cartridge approved for the L42 rifle. Yes. Any service issued and designated 7.62mm NATO specification cartridge. Any cartridge prohibited from use. Yes. Any non service pattern 7.62mm cartridge
Would this include specialized Long Range heavy ball or machinegun ammunition?Quote:
Originally Posted by Peter Laidler
Or would the "Nato Specification" cartridges be limited to Infantry rifle Ball?
The ammo marked as meeting the interchangeability standards of that time period.
Every source I've run across on these rifles stated that they were intended only for use with the 144 grain Ball.
Some Long range heavy ball ammunition in use in recent years did not exist when the L42 was still in service.
"Non Service Pattern" would likely include many of the Match Grade loads, even some National Match ammunition which has been used by US snipers ion the past.
Would you state that it would be safe to use M118 Long Range Special Ball in the L42 rifles?
By safe I don't mean just that the rifle would not blow up on the first shot, but rather that extended use would not damage or compromise the rifles safety margin, or that otherwise acceptable maximum variations in pressure levels, as much as 5,000 Cup higher than the standard 52,000 Cup would not be a concern.
PS
I'm looking at this question as this, rifles like the US Krag worked just fine with the original loads, but when a cartridge that on average generated only 3,000 CUP higher pressure was adopted some rifles suffered cracked or set back bolts.
The average pressure levels were far lower than proof test loads.
The rifles could easily handle a number of the higher pressure loads, but extended use put more stress on the bolts than its safety margin allowed for over the long haul.
Low Number Springfields were proofed at 75,000 CUP, yet extended firings could reveal hidden weaknesses years after they were proofed.
Winchester Model 1895 Rifles chambered for the .30/06 handled the original WW1 era 150 grain loads quite well, but when the slightly higher pressure loads of later years were used these rifles often developed excessive headspace.
The proof testing done by Winchester was officially accepted by the British government and no re proofs were required for those rifles sold in Britian in those days.
Some find it hard to believe but Americans actually used to drive on the wrong side of the road (left hand side) when we were a part of the Kingdom known as the colonies.Quote:
Originally Posted by villiers
When we kicked out King Georges army we switched to the method of driving on the "Right" side of the road like our new found friends "The French" .
Vive Le Libertad!
Would that have been true of ANY military rifle in service Peter - ie use the issued approved ammo and no other?Quote:
Originally Posted by Peter Laidler
You're dead right Prinz but look at the question and the next one too. Talk about loaded!!!!!!!!!! I am an Armourer and engineer primarily and not a chemist or a historian. What anyone chooses to put through a rifle after it's left my delicate little hands or Army service is a matter for them
Armourers are taught on day one
Armourers don't do ammunition and ammunition technicians don't do guns
I think the original poster's question has been answered. Once a thread gets too long, and the posters roam, they tend to cause my interest to wane as there are too many topics in that post to follow any rational discussion.
Perhaps it's time to end this one and carry any further topics of interest to a new thread.
Just my 2 cents worth :beerchug:
Besides, I'm getting that familiar tension in my gut that alerts me to the fact that moderation will soon be needed and then nobody's happy :surrender:
:lol:Quote:
Originally Posted by Amatikulu
Regards,
Badger
I agree with you Amatikulu about ending the mission and returning to base, the flack seems to be increasing and the ride is getting a little bumpy.
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All’s quite on the Western Front
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Difficult bolt handle lift seems to be a rather arbitrary reason to scrap a receiver. Based on that criteria many rifles would be scrapped for no good reason.
It is not uncommon for those who reload their ammo to occasionally lock up a rifle with a hot load. A large majority of those rifles are simply opened, the offending round ejected and the rifle remains in use with no damage.
In fact I have managed to make bolt handle hard to raise by jamming insufficiently sized cases in a chamber. All of this without firing a shot. It had nothing to do with Special Snoopy forgetting to wipe the oil out of his chamber.
Driving on the left hand side of the road is truly brainless.
Can you imagine trying to unsnap a girl friend's bra with your left hand while driving?
PS: I don't think Ed would be very good BBQed
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