colt / forster .223 field gauge?

[ARCHIVED THREAD] - colt / forster .223 field gauge?

Posted: 3/25/2015 12:03:55 PM EDT

Since the usgi field gauge with the ejector relief is hard to find, and expensive when you do find one, is there any reason not to chuck up a std field gauge in a lathe and kiss it with a toolpost grinder to put in the relief?

I assume they are hardened and wouldn't machine well with std tooling.

Posted: 3/25/2015 1:48:21 PM EDT

[#1]

You could disassemble the bolt quicker.

Posted: 3/25/2015 2:17:07 PM EDT

[#2]

Once, sure. But you'd always have the gauge, vs. always having to tear a bolt down.

Posted: 3/25/2015 7:41:07 PM EDT

[#3]

Any bolt with an ejector or an extractor should be disassembled for head spacing. The ejector plunger (or the extractor hook on an unmodified gage) puts a load on the gage that biases it to one side of the chamber, so the measurement is faulty, the error depending on the clearance.

Posted: 3/25/2015 7:59:31 PM EDT

[#4]

Understood. The USGI gauge is undercut at the base so the gauge does not contact either the ejector or the extractor. Is there any reason not to modify a colt / forster gauge similarly?

Posted: 3/25/2015 9:27:41 PM EDT

[#5]

I can't think of a reason as long as the base gives good contact against the bolt face.

Posted: 3/26/2015 11:20:22 AM EDT

[#6]

If you do this a Dremel with a cut off wheel would be quicker. If I understand correctly you are just relieving a spot, nothing critical as long as the ejector clears the spot (and you don't mess up the base/length of the gauge)

Posted: 3/26/2015 11:47:56 AM EDT

[#7]

This is what I'm thinking about.

Posted: 4/23/2015 2:54:41 AM EDT

[#8]

Yup....I managed to acquire this field gauge:

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Posted: 4/23/2015 9:34:25 PM EDT

[#9]

Quote History

Quoted:
Yup....I managed to acquire this field gauge:

http:// <a href=http://i125.photobucket.com/albums/p80/ewetstone/003_zpse4db4add.jpg</a>" />

http:// <a href=http://i125.photobucket.com/albums/p80/ewetstone/USGIfieldgaugespecs_zps570a15db.jpg</a>" />

View Quote

Do tell....I want one

Posted: 5/6/2015 12:23:39 PM EDT

[#10]

The Manson "Down and Dirty" headspace guages have that cut, and are $60 for a 3 gauge set.

[ARCHIVED THREAD] - colt / forster .223 field gauge?

Armory » Gunsmithing

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