.308 barrel marking
- Thread starter Deles136
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Preacherman
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I think that this refers to the fact that the original chambering for the Garand was .30-'06, which would be a "long" chambering in comparison to the .308, which is a much shorter round. I would assume that the warning "Short chamber" was put there to stop someone assuming that this was a "standard" Garand, and trying to load .30-'06 rounds into it.
A short chambered barrel means that the chamber is cut short (duh) and generally needs to be finish reamed in order to obtain proper headspace. This is done to ensure that you won't end up on the long end of (or over) the acceptable headspace range when you install the barrel - going on the theory that it is very easy to remove more material, but very difficult to put it back 
. The chamber should have been finish reamed when it was installed, but you may want to pick up a set of headspace gages just to be sure.
Rocko
. The chamber should have been finish reamed when it was installed, but you may want to pick up a set of headspace gages just to be sure. Rocko
Brownell's has them, though unless you get their "dealer" discount you can probably find them cheaper elsewhere. Most places that sell reloading stuff (sinclair, grafs, etc) should carry them. Forester makes the least expensive. IIRC, around $17 at brownell's w/o discount, $13-14 with.
There are three different types of gages - go, nogo, and field (from shortest to longest). The go and nogo are generally used for barreling - you want the bolt to close freely on the go gage, indicating the chamber is at least as long as the minimum spec. This gage is actually probably the one you are most interested in if you are worried about a short chamber not being finished reamed. The nogo gage is next - when barreling a receiver, you don't want it to close on the nogo gage. The nogo gage isn't at the maximum safe spec, but when installing a new barrel you want to leave some room for wear. The final gage, the field gage, is typically what most "end users" are interested in, as you are assuming the barrel was properly headspaced when installed and you just want to check for wear. It is the maximum safe chamber size for you to fire. If your bolt closes on a field gage, you shouldn't shoot the gun.
That being said, if you've already shot the gun and haven't had any problems, you are likely OK. If your chamber was really short, you probably wouldn't be able to chamber many rounds in a semi. If it was only a bit tight, however, you may be able to chamber most rounds, but the shoulder may get set back a bit and lead to excessive pressure.
Rocko
There are three different types of gages - go, nogo, and field (from shortest to longest). The go and nogo are generally used for barreling - you want the bolt to close freely on the go gage, indicating the chamber is at least as long as the minimum spec. This gage is actually probably the one you are most interested in if you are worried about a short chamber not being finished reamed. The nogo gage is next - when barreling a receiver, you don't want it to close on the nogo gage. The nogo gage isn't at the maximum safe spec, but when installing a new barrel you want to leave some room for wear. The final gage, the field gage, is typically what most "end users" are interested in, as you are assuming the barrel was properly headspaced when installed and you just want to check for wear. It is the maximum safe chamber size for you to fire. If your bolt closes on a field gage, you shouldn't shoot the gun.
That being said, if you've already shot the gun and haven't had any problems, you are likely OK. If your chamber was really short, you probably wouldn't be able to chamber many rounds in a semi. If it was only a bit tight, however, you may be able to chamber most rounds, but the shoulder may get set back a bit and lead to excessive pressure.
Rocko
Rocko - Thank you very much for the information about the headspace gauges. I am an old retired machinist but I am new to firearms. I have fired the rifle but there was some problem with the fired case being ejected with one live round. I wondered if the chamber was too tight and if I needed to use a finish reamer. I think the gauges will tell me the answer. Thanks again.
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