Hello

I am building my first AR upper.  The upper receiver is from Daniel Defense and so is the barrel.  My question is:  does anyone recommended that a chamber No-go gauge be used in testing the build.  I have seen AR builds on Youtube but have not seen anyone use it.  I thought the chamber spacing fixed based on how the AR barrel and receiver designed fit together.  Thanks for any replies.

IMHO a go-nogo gage is not required, especially with the Daniel Defense barrel. I did not use one on my build with an FN barrel and it works fine.

Vince

Plenty of info in the link below. The receiver has no bearing on the headspace, only the bolt and barrel. You can check the headspace before the barrel is installed (find the youtube video).

Headspace Thread

Forester gauges are less than $30 at Sinclairs (for some reason Brownell's charges more). They are cheap insurance to ensure the parts you have are in spec. mistakes in manufacturing happen.

Thanks for the link.

In addition to the headspace thread referenced above, there is a headspace discussion every couple of days in this space.
Although I have not seen a poll, my take is that most of us check headspace as a routine check.

Welcome to the site.

This, check it and be done with it or take that chance, most will pass, BUt you never know a set of guages is $50 , and/ or borrow a set or take the barrel/bolt to a shop and have them check it, its so simple it should be done IMO.

..but people wil lchime in and say they never have,,and good for them, everyone gas their opinion..

You are probably ok, but I prefer certainty so I check to make sure my builds will pass Go and No-go headspace specs.
Headspace is the distance from the face of the bolt to a datum point in the chamber, so an accurate check requires both bolt and barrel.
Bolts have specs also so different bolts may get different headspace readings.
Check before installing the barrel … better return options.
In my experience a barrel/bolt combination that fails will fail the Go gage.
A 5.56 NATO chamber might fail the SAAMI 223 REM No-go gage, but will likely pass the US mil-spec No-go 1.4706” gage.
My 18” DD 5.56 NATO barrel came in at 1.4656” – 1.4666” with my worst case loose bolt.
With the tightest bolt 1.4636” – 1.4646”.