Keyhole cause(s)

[PhillipM]

Bolt Action Rifles by Frank De Haas, p. 104 (about the British Enfield)
"Manufacturing tolerances for both rifles and ammunition were generous during the war, which in no way affected the rifle for military use."

The Springfield 1903 Rifles: The Illustrated, Documented Story... by William S. Brophy, p. 175 (about the development of the M1903-A3)
"Common in instances where it is necessary to fabricate parts of working mechanisms to close tolerances, both facilities mentioned found it difficult in certain instances to manufacture the finished components to the required dimensions shown on the revised drawings.....Resulting from this condition, a number of requests for liberalization of tolerances, originating with the reference facilities, were forwarded to the Office, Chief of Ordinance for approval."

The M1 Garand: World War II, by Scott A. Duff, p. 101 (regarding the development of the M1C sniper rifle)
"It was also discovered that the tolerances permitted by the engineering drawings were impacting the overall accuracy of the piece."

Not wanting to give up on my keyholing M1917 Eddystone, I spent hours searching the Net on how to gain accuracy from the M1917. I found many posts from guys who slugged their bores and found diameters ranging from .308 to .310. I found the same comments about bore diameter variance when researching the best handloads for the 30-40 Krag, which sometimes mic'd as large as .312. In the end, we're talking about 97-98 year old rifles that have had countless rounds run through bores that range from mint to sewerpipe; so, one guy's M1917 will put M2 Ball ammo into the 10-ring at 100 yds and another guy's will keyhole at 50 yds. With some persistence and a good reloading outfit, chances are if you try the right variables you can find a load that will hit the mark, saving you money on a new barrel and keeping whole a piece of US military history.

Requested.

I've requested Cathy Ireland to be my wife. Didn't happen.

[RC20]

Hopefully I can correct some of this.

1. If your rifle is key holing, there is something wrong, be it something at the muzzle, bore is a sewer pipe, no rifle would have been allowed out of the factory that key holed.
While there are a lot of possible causes, one to keep in mind is that ceremonial rifles that shot blanks a lot will eat out the throat. and yes I saw one like that, muzzle was pristine, the TE gauge went up to the hilt in the throat. Lesson, get a TE/MW gauge, that tells you a lot about any barrel be it 1917 or 30-06 (Seven Mathews makes them, calibrated for 1903 but good gauge TE wise on the 1917 though not exact)

2. Note the cracked Eddystone were WWII. Also note that if you put a WWII barrel on a W or an R, it would have done the same thing. Frankly I think its a sub set of the following issue (and attrition it to Chuck in Denver not me, but he does tons of these). note this is WWII not WWI. It should also have a HS, RI or JA barrel.

3. Cracked receivers are due to use of the wrong tool taking the barrel off. Its very possible they used the wrong tool. No one used an automatic tool of any kind in WWI for sure and WII to the best of my knowledge.

So either it was a local issue for bad work, previous bad receiver from same aspect or it was a numbers game and more Eddystone meant more chance for it to happen.

That's my take FWIW

Keep in mind that for all the talk of bad receivers in 1903, it was mostly a bad lot of ammo that had them blow up.