Bolt closing on field gauge

[mac1911]

I hear what your saying. Its comes across to me as
1. Go assures there is proper headspace
2. No go assures there is not excessive head space
3. Field tells you its still safe but nearing its serviceable limit.
Now if there is a spec there must be a limit to those specs reguardless of who makes the tools.....
So it should be if chamber is cut until go guage fits it should not close on a nogo period is the specs and tolerances can be that loose from one manufacture to the other why bother checking ? So that leaves only one thing. The manufactures just cram the reamer in there and cut to a point itshould not close on a field gauge. So nice and sloppy.....ohh the joy.

 

[1903Collector]

I hear what your saying. Its comes across to me as
1. Go assures there is proper headspace
2. No go assures there is not excessive head space
3. Field tells you its still safe but nearing its serviceable limit.
Now if there is a spec there must be a limit to those specs reguardless of who makes the tools.....
So it should be if chamber is cut until go guage fits it should not close on a nogo period is the specs and tolerances can be that loose from one manufacture tire to the other why bother checking ? So that leaves only one thing. The manufactures just cram the reamer in there and cut to a point itshould not close on a field gauge. So nice and sloppy.....ohh the joy.

Not reamer so much as when they set the barrel extension I think your confusing the two, if S&W sets headspace using PTG gauges (IDK what they use) and Joe shmo is checking with Forster gauges there could be a difference in the results they get, What I am saying is I don't think gauges are the same dimensions from manufacturer to manufacturer.

I am looking at a copy of the SAMMI chamber drawing:
Min headspace dimension = 1.4636
Max headspace dimension = 1.4736

 

[mac1911]

There must be some standard of tolerance right. Are we talking a plus minus of .? or .???? I know my foster gauges claim to be a plus minus of. 0003
So if a bolt closes on the Max side of tolerance of 1.4736 + .0003 I would consider the headspace to be excessive and to look for the problem.
If it didnt close on the Nato gauge spec. Of 1.4736 I would consider it safe.
So in the end if any of my rifles closed on a reputable manufactures Nato field gauge I wouldn't accept ....sometimes they will close and be ok.... maybe that's just my mind set though. I also get the mass produced mil spec good enough for government work side of it. Its just no fun when you measure something with a tool and it says "your headspace is dangerous" on new rifle. So now you loose confidence in both the tool and weapon manufacture?????

 

[1903Collector]

Mac, the 1.4736 gauge is not military, that is SAMMI max headspace dimension for 223, you should go to AR15barrels.com and poke around, their is a lot of good info on that site related to headspace ,gauges, etc.

 

[mac1911]

1.4736 is the colt field Max vs military 1.4730 per randells notes?
So the OP rifle closes on the colt field gauge he purchased
Two things going on. The colt gauge is manufactured wrong or his parts are not in spec.
For all purposes lets say gauge is correct...that means his gun is not safe....at this point I wouldn't trust either the parts or the tool and and consider something is not in spec. I hope the op gets to the bottom of it.

 

[ntomsw]

Any resolve to this yet?

 

[1903Collector]

1.4736 is the colt field Max vs military 1.4730 per randells notes?
So the OP rifle closes on the colt field gauge he purchased
Two things going on. The colt gauge is manufactured wrong or his parts are not in spec.
For all purposes lets say gauge is correct...that means his gun is not safe....at this point I wouldn't trust either the parts or the tool and and consider something is not in spec. I hope the op gets to the bottom of it.

I think were going in two different directions here.I do not dissagree that if the OPs gun is closing on a field gauge something is wrong!

 

[mac1911]

I think were going in two different directions here.I do not dissagree that if the OPs gun is closing on a field gauge something is wrong!

I understand. I was not in any way intending that. My comments are not directed at anyone. My communication skills might seem to lead into that?
I'm just more stumped at the large varience of specs.
Especially if its a new manufactured rifle from SW that's mil spec. To not close on a Nato nogo.
I would love to see the op bring that up with Smith and Wesson.
my Nato gauges where returned to day. I. Itching to check my factory RRA A2 Nato chambered rifle. My other 2 rifles are wylde chamber and expect them to pass the Nato gauges.

 

[Boarder700]

Finally got to talk to S&W today. Called twice, first time on hold for 15 minutes then hung up. Second time they answered after 20 minutes. I told the guy that I could get the bolt to close on a field gauge, he asked what problem that was causing. I told him I wasn't really sure but that I believed it was common knowledge that you shouldn't shoot a rifle that would close on a field gauge. He said that if I thought the rifle was unsafe he would send shipping info so that I could send it back and they could check it. Unfortunately, since I had to wait on hold for so long I had driven into an area with no cell service and my phone dropped the call. I also have an issue was a 442 that I didn't get a chance to ask about. I am going to try to email them rather than waste half an hour on hold again.

 

[Archilochus]

I told the guy that I could get the bolt to close on a field gauge, he asked what problem that was causing.

Wow, that's a pretty lame response from S&W. Does not inspire a lot of confidence in them.

Interested to see how this turns out.

 

[mac1911]

Wow, that's a pretty lame response from S&W. Does not inspire a lot of confidence in them.

Interested to see how this turns out.

the person on the phone might not have clue what a field gauge is ? The general response from CS service is to send it in if you feel the gun has a problem
.
Ok so I grabbed my RRA factory A2. I thought it was Nato chamber but its a wylde 1/9. Any how closed just fine on the clymer Nato go gauge. You would need a hammer to close on the Nato nogo guage. As its been with the 6 builds I did over the past few years with Nato chambered barrels.
Good luck to you OP. I hope you sent the gauge back and hope you get the Smith and your build right.

 

[1903Collector]

Any resolution to this?

On a side note, I bought a set of Manson gauges and re-checked my rifles that closed on my Forster no-go. None of them closed on the Manson no-go. I checked both gauges with my precision mic and there is .002 difference between them, the Manson being the longer of the two.