Caliber conversion for M1917 Enfield?


March 14, 2013, 07:43 AM

I have a pair of M1917 Enfields which I had never shot until pretty recently. I think they would be considered Very Good condition rifles, although I'm not sure if they have been arsenal refinished or anything of the sort.

Anyhow, one of the rifles has a nice bore, but it happens to have a rusted pit right about smack in the middle of the length of the body of the chamber. It's maybe an 1/8" in diameter and deep enough to leave an extrusion on fired brass and make cycling very difficult.

Is there anything that can be done to fix such a condition? Weld the pit and ream? The two answers I was thinking were to either A) buy a surplus barrel and have it installed or B) have the barrel re-bored to something with a little bigger case diameter and maybe bore diameter if the barrel has enough meat to support it. I wish to keep the external appearance and the remainder of the gun original. If I do go to a bigger casehead, I'd see about finding another bolt to modify to keep the original unmolested. The caliber swap is kind of appealing to me since I already have one in original .30-06 that shoots well.

So I'm curious, any ideas? Have there been any common calibers these have been converted to in the past? I think I read once that since the action was so long and stout, people had converted them to African magnum calibers such as .375 H&H in the yesteryears, but I don't know if that is true.

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March 14, 2013, 07:59 AM
Criterion makes mil-spec replacement barrels for the 1917 in 30-06 and 308. I've got one of their 308 barrels installed on my 1903-A3 and it's a great product. Not sure about the magnum calibers but this would allow you you to keep the original "look" of the rifle of you so desire.

March 14, 2013, 08:08 AM
I'd re-barrel the weapon. You'll be ahead and have a piece that will remain shootable for another century or more. To my limited mind, that rust pit might be point toward a deeper imperfection ~ maybe that even stemmed from the time of manufacture. I would want to chance putting a thinned-out version of that near my cheek myself. The 1917 in .06 is on my wish list.

March 14, 2013, 10:47 AM
Yes, that pit could be a flaw in the original blank.
It might hold fine for thousands of rounds, until it doesn't.
I wouldn't want to have it near my face when that happened...
Not trying to scare you, but it makes sense not to fire a powerful rifle with a flaw in the chamber.
I say rebarrel it and give it a new lease of life.

March 14, 2013, 11:40 AM
An additional endorsement for a mil-spec Criterion barrel. I put one in a 03A3 about a year ago. It's a great shooting barrel. I just got another one earlier this week to put in another 03A3 I'm rebarreling. The Criterion actually cost less than a new in wrap (NIW) GI barrel costs. The NIW barrels have gone up in price, driven by people who want a 100% GI rifle. Since the Criterion are not GI some purists are put off by them. However, if you plan on shooting the rifle I feel that the Criterion are a better way to go. They are accepted for CMP match shooting. In fact CMP also sells them.

The old barrels on Model 1917s are sometimes difficult to remove. You will need to find a smith that knows what they are doing. Also a good smith will inspect the receiver for cracks.

March 15, 2013, 10:03 AM
Many 30 caliber milspec rifles were converted to 308 Norma Magnum in the early 60's by simply reaming to the larger case and opening up the boltface. The massive 1917 Enfield action in 30'06 is a natural to convert, when dealing with a pitted chamber. I believe they can be converted to the 300 Winchester Magnum with little problem, and keep ammo costs down compared to the Norma round. A 180gr 30 cal bullet at near 3000fps is a potent round for all game in the lower 48.
I had a 1917 Enfield in the very long 300 H&H Magnum at one time, and currently have an FN M98 Mauser in 308 Norma, and I reload.


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