Lee-Enfield No4 Mk1 Strength?

[jkpq45]

Continuing my search for a suitably strong action for .30-378 Weatherby Magnum....

I have the opportunity to rescue a drill-demilled LEN4MKI. Think it's a good candidate for this rebarrel (assuming the welds, etc. done to demill it aren't prohibitively invasive on the receiver or locking lugs?

Thanks,
jkpq45

 

[Jim K]

I would strongly recommend against using a No. 4 action for the .30-378. That is a high intensity cartridge, with pressures running over 50k psi (some loadings will go into the 60k range) and with the large base the backthrust will be a lot greater than that of the original .303 British. The No. 4 is just fine for the cartridge it was designed for and other rounds in that pressure range, but going to a more powerful cartridge (assuming it were feasible) just is not, IMHO, advisable.

In addition, I strongly advise against trying to use any action that has been welded on. There is no way to tell how hot the action got, even if the welds seem to be in a small area.

Jim

 

[earlthegoat2]

No.

And once again, NO.

There is plenty of evidence out there of No 4 Mk 1 actions not even being able to withstand prolonged use of "hotter" 303 handloads. There is no way this would be sufficient for a 30-378 project.

Look to a magnum Mauser action or similar. Yes, I know these are expensive and there is reason for that expense.

 

[rcmodel]

A 1917 U.S. Enfield would be perfect.

A re-welded Lee-Enfield would shoot your eye out.
Probably the first shot.

rc

 

[dprice3844444]

http://www.6mmbr.com/actions.html#Stiller try here.you are playing in a dangerous area with those big cases,spend the cash for a quality safe action.

 

[Slamfire]

Lee Enfields operated at 40K psia. The action is not strong. Even though conversions were made to 308 Win, I have read posts that most receivers failed proof.

This action is so weak that the British NRA has given warning about No 4 Lee Enfield conversions and recommends that no No 4 be shot in the rain.

The action is so weak that it does rely on the tiny amount of case friction between case and chamber, which goes away if the case is wet.

You don't need to worry about shooting a Mauser, M70 or M700 in the rain, these are properly designed actions.


Based on this, I do not recommend Lee Enfield cartridge conversions, yours is wildly inappropriate.


http://www.milsurps.com/showthread.php?t=20339
This is the current stance of the British NRA safety warning which first appeared in the Summer 2009 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 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.

 

[Jim K]

To translate:

4150 bar is 60,190 psi
5190 bar is 75,274 psi
3650 bar is 52,938 psi

19 tons per sq in is 41,800 psi (British long ton)

Jim

 

[DMH]

Not to hijack this thread, but since the post is about the strength of the No4 Mk1 and the comment was made about not shooting it in any caliber in the rain my question is = Can an original in .303 cal. be shot in the rain or should it be avoided?

DMH

 

[rcmodel]

I'd say it certainly can.
The British seemed to sort of make it through two world wars and conquer half the third world with them, and I'm pretty sure they didn't call a cease-fire every time it rained.

Military rifles have to work in they rain, or they never would have been a blip on the radar then, or now.

The rain thing concerns rebarreled rifles converted to a higher pressure 7.62 NATO or .308 cartridge which was suspect in the first place.

It has nothing at all to do with .303 British chambered rifles.


rc

 

[DMH]

Rcmodel, thank you for the clarification.

DMH