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britrifles View Drop Down
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    Posted: November 10 2020 at 10:18am
Originally posted by Zed Zed wrote:

Personally I don't see re-proofing an old rifle to a higher pressure as good idea. 
It's a bit like raising the "red-line" on your classic car's engine so you can drive it faster! If there's no modification to make it handle the extra stress; it's not going to last very long!

I agree with Zed.  You are better off developing loads with mild pressures, about at the same pressure level as the Mk 7 .303 cartridge.  If you don’t reload, then try to find 7.62/.308 ammunition that is relatively mild.  That may be hard to determine since most manufacturers don’t list max chamber pressure for their cartridges.  

I’m sure I’ve said this before, but prior to each time I shoot my rifles I clean the chamber by wrapping a 3 x 1.5 in patch around a chamber brush and wet it in brake cleaner to remove all traces of oil and bore cleaner.  Keeping the chamber dry and free of oil minimizes stress on the action.  




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Post Options Post Options   Thanks (0) Thanks(0)   Quote The Armourer Quote  Post ReplyReply Direct Link To This Post Posted: November 10 2020 at 3:36am
Originally posted by britrifles britrifles wrote:

The only thing I agree with is that a wet or oily chamber and/ or ammunition does in fact increase bolt thrust loads.  However, the British method of measuring chamber pressure of cartridges and conducting proof tests at the time of the .303 and 7.62 conversions required the cartridge the be immersed in a light oil right before chambering.   

When I shoot in competition or in practice, I endeavor to keep rain off the cartridges and out of the action.  You will see a few MOA change in POI with wet cartridges vs dry, the other consequence of increased bolt thrust.  


Looking thru the old 'Instructions to Armourers' reveals a bit about the movement on POI.



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Post Options Post Options   Thanks (0) Thanks(0)   Quote Zed Quote  Post ReplyReply Direct Link To This Post Posted: November 08 2020 at 1:02pm
I have seen 7.62 Enfield conversions for sale in the UK that have been proofed to 20 tons instead of the standard 19tons as on my L39. I believe these recent re-proof's were to accomodate .308 factory ammunition. 
Personally I don't see re-proofing an old rifle to a higher pressure as good idea. 
It's a bit like raising the "red-line" on your classic car's engine so you can drive it faster! If there's no modification to make it handle the extra stress; it's not going to last very long!
It's nice to be important, but it's more important to be nice!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Goosic Quote  Post ReplyReply Direct Link To This Post Posted: November 08 2020 at 10:35am
...and now I understand a little more...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote The Armourer Quote  Post ReplyReply Direct Link To This Post Posted: November 08 2020 at 10:27am
Originally posted by Goosic Goosic wrote:

If anyone has Skennerton's big book, take a moment and read from page 256 to 264 and then reread the safety notice The Armourer supplied. 
The two topics cancel each other out.
To me it is as if two people got together one afternoon for tea and hashed out how to do,"this." Shake hands and leave.  They meet up the following afternoon for tea and proceed to hash out how to undo,"this." Shake hands and leave.

I totally understand the 7.62/308 controversy and I understand the controversy over conversions to 7.62/308 using the No4 actions based off of online debates and such. I also understand that if the rifle or ammunition does not conform to CIP standards, the rifle is basically trash, according to CIP standards. 
What I cannot understand is how a group of individuals can come up with a solution to a problem ,"updating the No4 from 303 to 7.62." And then basically 60 years later have a group of individuals condemn the solution unless the rifle goes through yet again more testing. Where does this end?

A long story, but the original NRA warning was due to 'pressure problems' using NATO ammunition.
Bisley provide the ammunition for the competitions (to ensure 'fair play') and they were issuing 'latest' NATO ammunition which has bigger (heavier) bullets and higher pressures. Tight leades meant that the bullets were too tight, meaning that the pressure was even higher.

Anyway - once someone realised that these rifles were prooved using 'standard' 144-150gr ammunition and original pressures they specified the pressure requirements and bullet / leade size, or have your rifle prooved for the higher pressures.

Hence the debate (pages ago) about using Higher spec NATO 7.62 in 'old' barrels and actions that were not prooved for those pressures.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Goosic Quote  Post ReplyReply Direct Link To This Post Posted: November 08 2020 at 10:06am
If anyone has Skennerton's big book, take a moment and read from page 256 to 264 and then reread the safety notice The Armourer supplied. 
The two topics cancel each other out.
To me it is as if two people got together one afternoon for tea and hashed out how to do,"this." Shake hands and leave.  They meet up the following afternoon for tea and proceed to hash out how to undo,"this." Shake hands and leave.

I totally understand the 7.62/308 controversy and I understand the controversy over conversions to 7.62/308 using the No4 actions based off of online debates and such. I also understand that if the rifle or ammunition does not conform to CIP standards, the rifle is basically trash, according to CIP standards. 
What I cannot understand is how a group of individuals can come up with a solution to a problem ,"updating the No4 from 303 to 7.62." And then basically 60 years later have a group of individuals condemn the solution unless the rifle goes through yet again more testing. Where does this end?
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Post Options Post Options   Thanks (0) Thanks(0)   Quote britrifles Quote  Post ReplyReply Direct Link To This Post Posted: November 08 2020 at 9:17am
The only thing I agree with is that a wet or oily chamber and/ or ammunition does in fact increase bolt thrust loads.  However, the British method of measuring chamber pressure of cartridges and conducting proof tests at the time of the .303 and 7.62 conversions required the cartridge the be immersed in a light oil right before chambering.   

When I shoot in competition or in practice, I endeavor to keep rain off the cartridges and out of the action.  You will see a few MOA change in POI with wet cartridges vs dry, the other consequence of increased bolt thrust.  






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Post Options Post Options   Thanks (0) Thanks(0)   Quote Goosic Quote  Post ReplyReply Direct Link To This Post Posted: November 08 2020 at 8:54am
Originally posted by Honkytonk Honkytonk wrote:

Excellent response to the article from the NRA. Sounds like a bit of anti-British invention and design, but interesting reading. If any of the members own No4's and live in an area that many get rain and are now afraid to take your rifle outside, I would would definitely give them a nice home!
I would also recommend that anyone who is now afraid to use their L39A1  or L42A1 because the Birmingham Proof Master has made these rifles an abomination according to the previous article, that you contact me for proper safe keeping and usage ...
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Honkytonk Quote  Post ReplyReply Direct Link To This Post Posted: November 08 2020 at 8:38am
Excellent response to the article from the NRA. Sounds like a bit of anti-British invention and design, but interesting reading. If any of the members own No4's and live in an area that many get rain and are now afraid to take your rifle outside, I would would definitely give them a nice home!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote The Armourer Quote  Post ReplyReply Direct Link To This Post Posted: November 08 2020 at 8:25am
This is the original article which had several No4 pictures included.

He concludes the article with :

"This post-war No.4 action is the best of the Lee Enfield bunch but if you overstress it you risk your life"


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Post Options Post Options   Thanks (0) Thanks(0)   Quote Goosic Quote  Post ReplyReply Direct Link To This Post Posted: November 08 2020 at 8:21am
 Is this part of a publication from the Ministry of Defense and what is rule 150?
I read everything word for word and line by line and this is what I make of it.
...in conclusion, if your Lee-Enfield No4 rifle is NOT in its original configuration of firing the venerable 303 British ammunition, you must discard of it post haste into the nearest dust bin...

I am truly not understanding what is being said here and does this apply to the thousands of DCRA converted No4 rifles, Sterling Armaments 7.62 mm conversion kits, the thousands of rifles converted by Gibbs and Charnwood as well and every L39/42A1 ever produced?
I am not trying to be obtuse but you seem to be supplying us here with only a fraction of the whole article. An open ended version if you will.  Where is the article that includes this elusive rule 150, or any other rule for that matter?
Are these Lee-Enfield No4  rifles,  according to the "Birmingham Proof Master," so poorly constructed that conversions to any other caliber including the 7.62x51mm NATO cartridge leaves them unfit to fire unless the,"Birmingham Proof Master" says otherwise?
Who or what is this Birmingham Proof Master?
A mean proof pressure of 5190 Bar and a Maximum Average Working Pressure of 4150 Bar is inconsequential to me unless there is a way to show the numbers in Piezo Scale form or the NATO EPVAT Mpa +25 tests.
I have spent countless hours converting this last No4 to fire 7.62x51mm NATO using an Ishapore barrel and my No5Mk1 was converted following the same procedure set forth from Charnwood C.O..
I am not a paid for your services gunsmith nor am I an armourer. I am very knowledgeable with the art of gunsmithing and was trained as such however.  I have no doubts that my rifles can and will safely fire the .308 handloads I have supplied for them for decades to come and no rhetorical BS will sway me otherwise. 


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Post Options Post Options   Thanks (0) Thanks(0)   Quote The Armourer Quote  Post ReplyReply Direct Link To This Post Posted: November 08 2020 at 8:06am
Originally posted by Honkytonk Honkytonk wrote:

"Owners of Enfield No4 actioned rifles in any calibre are strongly advised not to use them in wet weather or without removing all traces of oil from action and chamber prior to shooting." 
Good thing this warning wasn't published in the early '30's or we would all be goose-stepping and eating schnitzel!

There was an article in one of the shooting magazines which said very similar - I ended up with a huge argument with the editor but they would not issue a retraction, and refused to print my "letters to the editor".

This was my opening letter :


FAO Mr P. Carr (Editor)

                                     

Dear Sir,

 

Sporting Rifle – March 2010. “Wet Weather Drill”

 

As an ardent collector, shooter and historian of Lee Enfield rifles I was very concerned, even alarmed, at the statements made by Mr Chris White in his article “Wet Weather Drill”.

 

The article started innocuously enough but then seemed to move to a serious ‘Enfield Bashing’ session, with unsubstantiated rumours and half-truths being quoted as fact.

 

I would like to break down the article into manageable sized ‘chunks’ and look at each statement individually:

 

a)      “…….. at worst a stretched action. Lee Enfield’s are notorious for this.”

 

Any rifle with water in the chamber, or using wet ammunition will have problems. It is not that the chamber pressure is higher than normal, but, the fact that the cartridge case can no longer grip the chamber wall, and therefore more force is passed back onto the bolt head / bolt. As the author states himself, his grandfather was at Passchendaele, where conditions were not ‘ideal’ and I am sure if Enfield’s ‘exploded’ when wet there would have been some reports of it happening.

Where is the evidence confirming “No4 Enfield’s are notorious for this” ?

 

Out of around 16 million Enfields manufactured, surely it would have been known if there was a ‘problem’.

 

I have spoken with the most Senior British Military Armourer at the Small Arms School at Warminster. He has trawled the military records and can not find a single report of a No4 action being affected in this way. He has offered to discuss Mr White's findings with him if he should care to find out the truth, as opposed to ‘internet rumours’.

Contact details provided if you require them.

 

b)      “A No4 shooting 7.62 ammunition is already doing a job beyond its design parameters”

 

Whose design parameters? As well as civilian shooters, the Military and the Police have used No4 actioned 7.62 rifles for many years. For example, the L39 (Military target rifle) was designed and built by RSAF (Royal Small Arms factory) Enfield, the Police ‘Enforcer’ Sniper rifle, The Enfield ‘Envoy’ and numerous other rifles were built by RSAF Enfield and Parker Hale, is Mr White suggesting that they knowingly built and sold rifles that were being asked to perform beyond their design parameters? I think the RSAF would have a little more knowledge on this subject than Mr White.

 

c)      “This coupled with questionable gunsmithing and significantly undersized bores when the rifle was converted from .303 ……”

 

Undoubtedly there have been some ‘home conversions’ of Enfield rifles but to lump together all conversions, as “questionable gunsmithing” is totally unreasonable. Official ‘conversions’ have been undertaken by Government agencies all around the world, again such notable names as RSAF, Parker Hale, and DCRA, - the list goes on.

The comment could be read as the fact that the 303 barrels were bored out and sleeved for 7.62 – this is not the case. “Conversion Kits” included the correct (newly made) barrel, breeching up washers, bolt head and extractor, there was no ‘questionable gunsmithing’ involved.

What evidence has Mr White to support his claims of “questionable gunsmithing” & “undersized bores” ?

 

d)      “….. stressing the action beyond this limit has a cumulative effect, which ultimately leads to failure …….”

 

Absolutely true of any metal part, on any rifle and is not a peculiarity of an Enfield rifle.

 

e)      “…. To cap it all, when the rifle passed into civilian hands it was subject to a deliberate overload at the proof house …..”

 

The implication here is that this is something unique to Military surplus / Enfield rifles, surely Mr White is aware that ANY firearm sold in the UK must be proofed with a “deliberately overloaded” proof round.

The military proof testing (STANAG) is even more severe than the civilian testing in that not only do they use a proof round 25% above service pressure, but they also use an ‘oiled’ round (to simulate wet cartridges) which would pick up on the alleged “action stretching”.

I quote from the specification:

 

“Each weapon and component considered vulnerable to the effects of a rapid change in pressure, for example barrels, breech blocks and bolts, will be tested by firing one dry round at a corrected minimum of 25% over pressure and one oiled round at a corrected minimum of 25% over pressure. 25% over pressure means 25% in excess of the Service Pressure (Pmax). The Service Pressure is defined as the mean pressure generated by the Service Cartridge at a temperature of 21°C. Such a high pressure proof is conducted with both the weapon and ammunition conditioned to an ambient temperature of 21°C.”

 

Any military firearm would be subject to this test, I again revert to the example of the Military L39 which is a 7.62 calibre ‘converted’ No4 action.

 

 

The shooting fraternity is under increasing pressure from Politicians and the non-shooting public, and ‘scare mongering’ reporting such as this article does our sport no good at all.

With the latest mandates from the UN to ban the civilian sales of military calibre weapons and ammunition (this includes 7.62), The international airlines (IATA) refusing to carry military calibre weapons, and the fact that in the UK 7.62 and .308 are seen as the same calibre (and many FAC’s show 308/7.62) we are looking at an uncertain future.

 

I am sure Mr White has researched his article and used information from qualified sources, this being the case, I see no reason why he should not be able to provide empirical evidence to support his article, If he cannot, then I would ask that an admission of error be published.

Yours faithfully


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Post Options Post Options   Thanks (0) Thanks(0)   Quote Honkytonk Quote  Post ReplyReply Direct Link To This Post Posted: November 08 2020 at 7:47am
"Owners of Enfield No4 actioned rifles in any calibre are strongly advised not to use them in wet weather or without removing all traces of oil from action and chamber prior to shooting." 
Good thing this warning wasn't published in the early '30's or we would all be goose-stepping and eating schnitzel!
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Post Options Post Options   Thanks (0) Thanks(0)   Quote The Armourer Quote  Post ReplyReply Direct Link To This Post Posted: November 08 2020 at 7:23am

Just for 'interest' (I knew I had it somewhere)

A few years ago - Notice from the NRA banning the use of LE No4s in 7.62 unless ........................

NRA Safety Notice re No 4 7.62mm Conversions

This is the current stance of the NRA safety warning which first appeared in the Summer NRA Journal:

Safety Notice
Enfield No 4 Rifle Conversions to 7.62mm


A safety warning concerning the use of Enfield No 4 Rifle actions converted to 7.62mm was published in the Summer 2010 Journal.

After further consideration of all factors influencing safety of these conversions and consultation with the Birmingham Proof Master, the following advice must be adhered to in respect of the use of Enfield No 4 conversions:

• Owners of Enfield No 4 actioned rifles converted to 7.62mm currently proofed to 19 tons per square inch are strongly advised to have them re-proofed to the current CIP standard (requiring a minimum mean proof pressure of 5190 bar) which allows the use of CIP approved ammunition with a Maximum Average Working Pressure (MAWP) of 4150 Bar.
• Conversions retaining their original Enfield barrel or a replacement barrel as manufactured by RSAF Enfield are safe to use with commercial CIP approved ammunition, which complies with a MAWP of 4150 bar, loaded with any weight of bullet, providing they carry a valid proof mark, and are still in the same condition as when submitted for proof.
• Conversions fitted with any other make of barrel (such as Ferlach, Maddco, Krieger etc) should be checked by a competent gunsmith to determine the throat diameter of the chamber/barrel fitted before use.
• Conversions where the throat diameter is less than the CIP specification of 0.311” but not smaller than 0.3085” must not be used with ammunition which exceeds 3650 Bar MAWP when fired in a SAAMI/CIP pressure barrel.
• Conversions which have been checked and found to comply with Rule 150 may safely be used with any ammunition supplied by the NRA including the 155 grain Radway Green Cartridge, 155 grain RUAG Cartridge or any other commercial CIP Approved cartridges loaded with bullets of any weight provided that the ammunition pressure does not exceed 3650 Bar when measured in a CIP standard barrel.
• Owners of Enfield No 4 actioned rifles converted to 7.62mm who are uncertain as to the proof status of the rifle should have it checked by a competent gunsmith.
• Owners of Enfield No 4 actioned rifles in any calibre are strongly advised not to use them in wet weather or without removing all traces of oil from action and chamber prior to shooting.
• Enfield No 4 rifles which are fitted with a barrel which has a throat diameter less than 0.3085” must not be used on Bisley Ranges.
• Ammunition loaded with bullets of any weight which are of greater diameter than the throat diameter of the barrel must not under any circumstances be used on Bisley Ranges in any rifle or barrel of any manufacture.

 



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Post Options Post Options   Thanks (0) Thanks(0)   Quote britrifles Quote  Post ReplyReply Direct Link To This Post Posted: October 27 2020 at 12:46pm
Zed, nothing wrong with your thinking here, lighter loads will be easier on you and the rifle and provide longer barrel life and less receiver/bolt wear. 

I’ve tried to explain the difference between loads that are within the action and barrel strength safety margin (which includes the headspace issues) and long term durability of the barrel and action.  What may be a perfectly safe load for a new rifle, these commercial .308 loads can accelerate wear and erosion of the barrel as compared to light loads that we assemble.    If you shoot 10 rounds a year, you won’t cause much wear shooting .308 commercial ammunition that has chamber pressures within the capability of the No. 4 action, but if your like me and shoot several thousand rounds a year, you will get much longer life with reduced loads, and they are just as accurate (possibly more accurate) than the full power .308 load in a No. 4 Enfield.

Yes, the 7.62 NATO special ball Mk 316 was developed for sniping, for modern military bolt and auto loading rifles that shoot 7.62 ammunition.  I’d suspect that the sniper bolt action rifles have fairly tight headspace (likely within .308 SAAMI specs) while the autoloading rifles likely have slightly longer headspace.  


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Post Options Post Options   Thanks (0) Thanks(0)   Quote britrifles Quote  Post ReplyReply Direct Link To This Post Posted: October 27 2020 at 12:30pm
Frameman 1, I would consider that Hornady brass to be in the “light weight” .308 commercial brass category and not suitable for your chamber.  Not the lightest I’ve seen, but other commercial brass such as Lapua is heavier (approx 175 gr).  That is a fair bit of elongation of the Hornady case on firing.  


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