most what's the most commom cause of excessive m1 headspace?

[Ron H.]

Sir, IMHO the most common cause of incorrect headspace in M1 rifles is indiscriminate bolt-swapping. Swap bolts all you want, but use headspace gauges when you do it.

Hope this helps, and Semper Fi.

Ron H.

Information

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[goo]

i myself don't awap bolts indiscrimately. i do in scriminately. nobody ever accused me of having too much headspace.

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http://farm4.static.flickr.com/3630/...3d6eb1.jpg?v=0

[slamfire1]

I am going to assume the chambering reamer cut the chamber to a proper headspace. I don’t see the shoulder moving due to hot powder exposure.

8620 was used in the construction of M1 Garand parts. While it is not some Uber super material, it is a good material and has a decent ultimate and yield strength. The case hardening on these WWII vintage receivers is exceptionally thick. I don’t know how you would wear through the case without an abrasive. And the receiver metal is not going move.

If you are swapping bolts around and finding that headspace is different, well welcome to tolerance stackup.

The Swiss are the only people that I know, who made a service rifle (the K31) in which all bolts are fully interchangeable throughout all rifles for the entire production.

As for Winchester. Winchester would be in a Production Engineering class, the "bad" example of manufacturing process flow and control. I heard there was a time when M1 Carbines deliveries were halted, because Winchester carbines were so poorly built.

Springfield Armory parts are very good. Throughout the entire production of the Garand.

Maybe if Winchester was run more like Springfield Arsenal, Winchester would still be making excellent rifles.

[garand poobah]

i do in scriminately

nobody ever accused me of having too much headspace.

lol, these are both very good.

if a reciever were to be worn, couldnt the rifle be rebarreled and just finish chambered to fit?

[Devil Dog]

"if a reciever were to be worn, couldnt the rifle be rebarreled and just finish chambered to fit?"

Most Commercial barrels are short chambered (aprox. .010") enough that finish reaming would correct a headspace problem caused by the receiver/bolt wear.
However, USGI barrels are already "finish reamed" and usually will not correct a headspace problem caused by a receiver/bolt

[mhb]

However, USGI barrels are already "finish reamed" and usually will not correct a headspace problem caused by a receiver/bolt[/QUOTE]

for the M1 (not those from previously used rifles, which may still be found serviceable after inspection and gauging), as with the 1903, are short-chambered to be finish-reamed to correct headspace with the receiver and bolt used in rebuild. This is necessary to insure that bolts and receivers which both pass gauging and are acceptable for rebuild do not result in excess headspace due to cumulative tolerance which is still within the acceptable range for each part, but may result in the assembled headspace being near the maximum permissible, when it is desired that new and rebuilt rifles have headspace near the minimum, for longest service life.
mhb - Mike

[Gus Fisher]

Indiscriminate swapping of bolts without using correct headspace gages is the most common cause of Headspace problems in Garands. Too many people believe you can just swap any old bolt in any old rifle.

A new bolt will be good for at least three to five barrels.

A new receiver will be good for at least 5 to 8 bolts.

Headspace only "grows" at most one to two thousandths of an inch over the entire course of the life of the barrel and some barrels you won't see any difference at all in the headspace.