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)