.303 norma magnum

[kevin.303]

i know a guy through technical college who is a gun smith. he has a custom rifle he wants to dump cheap so he doesn't have to register it. it's a p-14 enfield rechambered to .308 norma magnum. then the case is necked up to fire a .303 (.311") bullet. he calls the result a .303 norma magnum. has anyone heard of such a project, and would this be something good to grab?

[PaulS]

Kevin303,
I am no expert on the Enfield action but I would be suspect of it. The bolt thrust is going to go up even if the pressures remain the same and if the pressures go uptoo the action may not be strong enough to withstand the thrust on the bolt - Maybe someone can join in here with some actual knowledge.

PaulS

[John Traveler]

Kevin,

That ".303 Norma Magnum" sounds like strictly a BAD idea.

The late great P.O. Ackley, renown authority on rifles, actions, rebarreling, and wildcats, etc. stated several times that rechambering of the P/14/P17 "enfield" rifles with original military barrels was not recommended.  The Norma Magnum cartridges are much longer and larger in diameter than the standard .303 or .30-06 cartridges, and leaves the forward end of the barrel chamber wall too thin.  He described examining rifles with buldged chambers and hard extraction from firing only a few rounds.

The same advice has been given many times for NOT rechambering the SMLE .303 for "improved" cartridges, for the same reason.  the stock military barrels are relatively thin over the chamber and chamber throat areas.

HTH
John

[John Traveler]

Kevin,

I just wanted to make sure that I did not give you the wrong impression on the last posting.

the P14 and US M1917 "enfield" actions are ideally suited for building nice magnum rifles, but only if they are properly rebarreled using modern steel barrels of accepted sporter dimensions.  That long action and large bolt face makes it close to perfect for the "magnum" series belted and non-belted cartridges.  I've done several, and have fired many of the same.

The problem with that re-chambered ".303 Norma Magnum" is that the commonly available fixed pilot chambering reamers used in a .303 bore will give a BAD case of "non-concentric chamber" in addition to the thin chamber/throat area mentioned earlier.  If your intention is to properly re-barrel the action, then it is a good choice.  
What that boils down to is how much of the work you can do and how much of it needs to be done by a qualified gunsmith.  In other words, that "bargain" may not look like such a bargain when you add up all the costs of making the rifle look and shoot right.

What are you studying in trade school?  I've visited Winnipeg several times, and was not aware of any gunsmithing schools.

John

[kevin.303]

i am studying industrial matainence at the winnipeg technical college

[Downwindtracker2]

The P-14 used nickle steel like late numbered Springfields , Winchester M-54,M-70 pre-war,and Remington M-30.The steel is as good as the others.The Model 1917 and Remington M-30,M-720 are the same basic rifle.The gas handling of the P-14,P-17 and M-30 is not as good as the mauser or even the pre-64 M-70.Since the barrel  has been removed to rechamber,it is worth while to check the receiver for cracks,some barrels were so tight the gunsmiths cracked the receivers taking them off.I have a P-17 rechambered to 308Norma that shots 5/8" groups,they would be smaller if I could shoot better.Hope this helps.

[Grey Dog]

There is absolutely no problem with the Enfield barrel dimensions as far as wall thickness is concerned. Measure one and compare it with a featherweight M70 for instance
The only potential problems with the use of 311 bullets in the Norma case would be:
1. Insufficient neck clearance in the chamber. In reality this is unlikely since the chamber specs allow for a generous neck.
2. Insufficient throat. Depending on the reamer used the throat may be too small for the 311 bullet which would tend to raise pressures somewhat. Ideally the chamber throat would have been cut seperately with a 311-312 dia throater.
The undersized pilot concern is not a concern if the barrel was properly set up to do the job in the first place. If the barrel runs concentric, the chamber will be concentric providing the reamer starts out that way.
By the way, this conversion was not all that uncommon when the 308 Norma was in it's heyday. GD