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This is so great! Thanks for making my day. Sharing the hits on steel was perfect.
Gotta get mine up and running now.

Ed
 

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The debate regarding pressures of milsurp 7.62x51 rifles occurs frequently in the Mauser area. It is actually easy to address. First you should learn to reload. Problem fixed. Starting loads for the .308 are appropriate and even better just turn to the load section for the 300 Savage. 300 Savage ballistics are more than adequate for most purposes. The 7.62x51 has its origins from the .300 Savage. No way you say. Way I say. That was the beginning of the NATO round.
 

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That Aussie document is suspect IMHO. In what universe is the 7.62 NATO pressure 47k CUP? The lowest estimate I've ever seen is 50k CUP. I've been down this road before, so below is what I posted on another forum. Can (do?) people load .308 to within an inch of its life? No doubt. Is this a bad plan for converted Mausers and 2A/2A1s? Quite likely. Do I think this can be an issue with commercial .308 Winchester and surplus 7.62 NATO? Not so much.

A more complete set of thoughts:-

Doncha just love how certain inaccuracies become fact and refuse to die no matter how many times the truth is spoken. Yes, it's 7.62 NATO vs .308 Winchester AGAIN. Shooting Times trotted out the old fiction about .308 Win being a 62,000 psi cartridge and 7.62 NATO is only 50,000, so has much less pressure. WRONG,WRONG thrice again WRONG.

The 62,000 psi figure for 308 Winchester is the latest SAAMI pressure measured using a piezo pressure transducer. The value for 7.62 NATO comes from an old Copper Units of Pressure (CUP) style measurement, and the answer is indeed 50,000 CUP. It's like saying the distance between two points is 62 miles and somebody says, "No, it's much further, like 100 km". Unfortunately there is no "laws of physics" based PSI to CUP conversion, but empirical data does show a relationship. http://www.shootingsoftware.com/ftp/psicuparticle2.pdf

Shortly, somebody will appear and say "Ah, but it's 50,000 psi CUP". There's no such unit of measure. It's like measuring your inseam in grand pianos per decade. Don't go there.

If you compare .308 Win and 7.62 NATO as specified by the European standards folks at CIP, Commission Internationale Permanente pour l'Epreuve des Armes à Feu Portatives - Wikipedia, the free encyclopedia, lo and behold they are both rated at the same pressure. C'mon now, you're not really surprised, are you?

Yes, the SAAMI spec for the .308 Win CASE is not the same as that for 7.62 NATO. The latter has thicker walls at the head for use in automatic weapons with generous headspace, so it has a little less capacity than .308 Win. Big deal. Go look at the velocity specs listed by any of the big manufactures and you will see they are usually identical for bullets of the same weight. Does that sound like the extra case capacity is making much difference, or that one runs at 20% more pressure than the other? No, it doesn't work for me, either.
 

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I'm not going to discuss the pressure issue. It very well could be valid. And there is the issue of the case differences. So, I'll be using 7.62.

There is, however, one salient issue that stares out at you from the documents: they specifically address .303 rifles that have been converted to 7.62. There were indeed Mk.III*s that were converted to 7.62, but the 2A1 wasn't one of them. The 2A1 action was redesigned from the ground up as a 7.62 action. They went to a stronger grade of steel, specifically to accommodate the redesign. I understand that even that comes into doubt because Ishapore was just catching up with the rest of the pack of Lee-Enfield builders.

All can be true. BUT, no-one seems to notice the elephant in the room that the document is addressed to a class of Lee-Enfield that the 2A1 is not a part of. It is not converted. Re-read the notes.

But, I'll be using 7.62.

Bob
 

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The 2A1 action was redesigned from the ground up as a 7.62 action. They went to a stronger grade of steel, specifically to accommodate the redesign. I understand that even that comes into doubt because Ishapore was just catching up with the rest of the pack of Lee-Enfield builders.
Unfortunately that is another internet 'fact', plucked out of thin air with no evidence, it spreads like wild-fire until it become the "Holy Gospel according to St.Internet".
Even well known authors and historians are convinced, after all, they can only repeat what 'is known at the time' (Hindsight is a wonderful thing).

Hopefuly, if posted enough times and repeated by all the converts, the 'New Truth' will itself become fact.

With regard to the 2A being a 'conversion' Peter Laidler, whilst at the Small Arms School, purchased 12 Ishapore 2A / 2A1 rifles and had them tested for metalurgy at a university - it was found that, within specification tolerances, the steel was identical to the No1 Mk3 - but - of interest was the fact that under the microscope could be seen the traces of the original markings that had been scrubbed. Yes, you guessed it. some of them were actually No1 MK3 conversions. Some will argue slight differences in measurements. shape etc between the No1 Mk3 and the 2A / 2A1 but assuming Peter is correct, at least a number were actually conversions.

I have posted this several times previously, but have no hesitation in doing so again.

Summary ;
1) After independance Ishapore changed the specification of the No1 Mk3 steel to an inferior grade and the rifles failed proof testing, so they changed the proof test until it passed.
2) The 2A was manufactured using the same 'low quality' steel and the rifles beacme totally unusable,
3) For 2A production they reverted back to the 'better quality' (as originally specified for the No1 MK3) steel and the rifles just passed proof testing. You could, I suppose, argue that the 2A uses a 'stronger grade of steel' but in truth it is the 'originally' specified steel.

Anyway - the source, and the book is still available on Amazon should anyone wish to have their own copy

Gun Digest 33rd Anniversary 1979 Deluxe Edition: The World's Greatest Gun Book: Amber, John T: 9780695812003: Amazon.com: Books


Extract from “Gun Digest 33rd Anniversary 1979 Deluxe Edition”

The article covers a host of subjects (and several pages) based around the Indian firearms industry and more specifically the ‘Proof House’,and includes such stories as how, when the proof master was away for some time, they decided to proof test 20 gauge shotguns with 12 gauge proof rounds because nobody had any 20 gauge rounds - and many other nighmares - but - of particular interest are a couple of paragraphs regarding ‘Enfield’s’.

Article Author : Mr A G Harrison

Qualification : Former ‘Proof Master’ of the ‘Rifle Factory Proof House, Ishapore, India’


From 1908 to 1950 all military bolt action rifles made at Ishapore were proof tested with a dry-round, followed with by an oiled proof round. The proof cartridge was loaded to 24 tons psi breech pressure, or 15% higher than the service pressure. In 1950 (after the departure, of India from British control) the material for the rifle bodies was altered from an EN steel to SWES 48 steel with the recoil shoulder and cam recesses being heat treated. With this change the rifle receivers distorted when oiled proof cartridges were fired. This was discovered when hard and sometimes impossible bolt retraction was experienced. Large quantities of rifles were rejected.

To avoid rejections the authorities ordered discontinuance of the oiled proof round. Therefore from 1950 to the end of SMLE production, rifles made at Ishapore were proof tested with one dry proof only, although the specification still called for both dry and oiled proof. All bolts and bolt heads issued as spares were always proofed with a dry proof round only.

A bolt action rifle similar to the SMLE MkIII*, modified to fire the 7.62mm NATO cartridge, was produced at Ishapore, first in February 1965. The receivers were made of SWES 48 steel (as per the SMLE MkIII*) and with the NATO proof cartridge the receivers were found to distort with both the dry and oiled proof round. The material was changed back to the EN steel so now the rifles stand up better to dry and oiled proof. After passing proof the barrels are impressed with the Indian national proof stamp. The bolt handles and bolt head claws are struck with the crossed flags only.



Screenshot (508)_LI.jpg
 

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It's like measuring your inseam in grand pianos per decade.
I think you owe me a keyboard for that! I hosed mine through the nose with Coke!
Which is colder 32°F or 0°C?
 
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Discussion Starter · #30 ·
Sounds like a good day outing 👍🍻
I can’t help noticing (maybe me eyesight again 🤔🤷‍♂️) is the that a dog leg on the rear sight protecter on the left side?
Cheer’s.
Hello,
I dont know what a dog leg is Sir, but the rear sight is the one graduated to 800. I have an RFI 2A with the older SMLE rear with a different rear sight profile and graduated past 800. I'm thinking of taking that to the range this weekend and see if it performs as well as Gupta.
:)
 
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Hello,
I dont know what a dog leg is Sir, but the rear sight is the one graduated to 800. I have an RFI 2A with the older SMLE rear with a different rear sight profile and graduated past 800. I'm thinking of taking that to the range this weekend and see if it performs as well as Gupta.
:)
No worries mate I’m just not trusting of me eyesight these day’s.
Cheer’s & good outing 👍🍻
 

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I think its just a shadow from the opposite front sight protector? Being squared not rounded they look different.

A "dogleg" is an intentional bend or kink in a lever or rod. Like this Pat 14 bolt handle. Its called that because it sort of resembles the shape of a dogs hind leg.
3854975
 
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Good name for one.
The SMLE with its "Pugnacious stubby snout" fits it well"!
 
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