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  #21  
Old 12-23-2010, 12:44 PM
vetterli vetterli is offline
 
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My- NIW barrel fit perfect, didnt have to ream
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  #22  
Old 05-04-2011, 09:49 AM
Silver Shamrock Silver Shamrock is offline
 
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Ericc
thanks for this thread. I just bought a 12-SA bolt for my 2.0 SA. checking out the headpsace on a 12-43 barrel and it closed on the NO GO gauge I have. I'm thinking "crap - a bad bolt". Checking here I now know I need a FIELD gauge to verify if the headspace is bad or not. I have a 19-SA bolt that was verified to be good by gunsmith. So its off to the store for a FIELD gauge - less money than another bolt.
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  #23  
Old 05-04-2011, 12:27 PM
Unclenick Unclenick is offline
 
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If it's a new bolt you want the NO GO gauge in order to leave some room for the bolt lugs to settle in a little. A FIELD gauge is used when the bolt and receiver have worked together for a bit. An alternative would be to use the FIELD gauge, but keep checking periodically to be sure you didn't grow past it as the lugs settled.
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Last edited by Unclenick; 05-04-2011 at 12:31 PM.
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  #24  
Old 05-04-2011, 01:15 PM
Silver Shamrock Silver Shamrock is offline
 
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Everything's been used....12/43 barrel with a TE of 4, 12-SA bolt that's also been used. So we'll see.
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  #25  
Old 05-04-2011, 01:27 PM
Unclenick Unclenick is offline
 
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Still, you want the bolt settled in your receiver. May not match the one it was in, so more settling could occur.
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  #26  
Old 02-12-2013, 02:15 PM
TGR TGR is offline
 
Join Date: Jan 2012
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Got a new correct bolt for my Garand. Bolt closed on Go and No-Go Gauges. Guess I need a field gauge? Interestingly, it also closed on the bolt that came with the gun from the CMP that I have been shooting with over a year..

Original '44 Barrel, and Clymer Go/No-Go Set.

Any suggestions?
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  #27  
Old 02-12-2013, 02:31 PM
Ericc Ericc is offline
 
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Quote:
Originally Posted by TGR View Post
Got a new correct bolt for my Garand. Bolt closed on Go and No-Go Gauges. Guess I need a field gauge? Interestingly, it also closed on the bolt that came with the gun from the CMP that I have been shooting with over a year..

Original '44 Barrel, and Clymer Go/No-Go Set.

Any suggestions?
Until you test with a field gage you really can't come to any conclusions yet. When you used the gages you just used finger pressure on the bolt?

Bolt is stripped, no operating rod spring, etc..

Eric
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  #28  
Old 02-12-2013, 03:27 PM
TGR TGR is offline
 
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Quote:
Originally Posted by Ericc View Post
Until you test with a field gage you really can't come to any conclusions yet. When you used the gages you just used finger pressure on the bolt?

Bolt is stripped, no operating rod spring, etc..

Eric

Took the ejector out, but left the bolt assembled. Tried with Op Rod and No Spring and without Op Rod as per CPM Tech Websight. Bolt fell right into place.
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  #29  
Old 02-12-2013, 03:37 PM
Ericc Ericc is offline
 
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Quote:
Originally Posted by TGR View Post
Took the ejector out, but left the bolt assembled. Tried with Op Rod and No Spring and without Op Rod as per CPM Tech Websight. Bolt fell right into place.
You can do a quick survey with your no-go gage. Place a piece of blue painters tape on the bolt end of the no-go gage. Trim the tape so it doesn't wrap over any edge. it should be a flat little circle.

Then try again with the gage. The tape is a poor mans way of lengthening the gage a little. Add tape until the bolt doesn't close and then measure the thickness of the tape.

Add the tape thickness to the no-go dimension and see if it's less then the field measurement.

This isn't terrible accurate but it should get you in the ball park until you can pick up a field gage.

Eric
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  #30  
Old 02-12-2013, 06:51 PM
TGR TGR is offline
 
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So if it closes on a field Gauge, do I look for a bolt with less wear? Or are we talking a barrel issue?
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field, gauge, headspacing, no-go

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