Which gauge is the best to check headspace no go or field?
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Which gauge is the best to check headspace no go or field?
I use the Go & No Go. I have encountered one rifle where the bolt failed to close on a Go gauge & it had to be finish chambered. I prefer the No Go vs. the Field Reject gauge as the tolerance is tighter; if there is a problem, I'd like to know about it "sooner rather than later".
Go and No-gos are used when you are working on a gun. If you are fitting a new bbl or a new bolt ( or even used , but new to that reciever), those are what you want to do a good job. The field gauge is for when the parts have become worn and you want to be sure that the wear has not reached a point where safety is being compromised. If you are buying a used gun and can only afford one gauge , the field is what you want. Chris
As "emmagee1974" said, if your talking about checking headspace on a used M1 Garand then go with the "FIELD GAGE".
If you are installing a new barrel, and reaming the chamber you need all three. If you are swapping bolts with that oh so hard to find and expensive, original XTYZ squiggle mark, you need a field gauge and some string to tie the rifle onto a tree to fire it before it blows up in your face.
Your mileage may vary.
If the rifle passes the field guage there is no problem. The bolt is tight enough. It is safe, it does not affect accuracy, and head space changes very little over time, even with lots of rounds fired.Quote:
Originally Posted by Kirk
I have both a NO GO and a FIELD. It it fails the NO GO it might still be OK, but you need a FIELD to know. If you have a choice of several bolts that are safe (pass the FIELD) but you want to pick the "best" one (smallest acceptable headspace for less brass wear) you need a NO GO. That's why I have both.
You will still be "information short". If it does not close on a field and does not close on a no-go , you still will not know if it will work till you check it on a "go" gauge. For what you are doing , you need all three. If you are buying a used gun you should have all three because you do not know how long the parts of the gun you are looking at have been together. If you know the gun has been shot "as it is now in your hands " , then you know it should close on a go ( that's how it got in the used condition). Being used , it may close on a no-go. If it does not , that's good , if it does , it tells you little. The field is the deciding one, the buy it or leave it test , and therefore the one to have if you can have only one. Chris
I understand what you are saying, and I agree that if you only have one the FIELD is the most useful. In my opinion a GO gauge is useful if the rifle has a new (as in brand new) barrel, but otherwise isn't essential for me, as I have no brand new barrels that might be short chambered.Quote:
Originally Posted by emmagee1917
Since I take the bolt apart to check headspace, and there is no firing pin, I use a M2 round as my GO gauge. Again, disassembled bolt with no firing pin, just receiver, barrel and bolt for the test, no stock, trigger group, op rod, etc.