AR Sponsor
Posted: 10/28/2013 6:32:43 PM EDT
|
I am currently in the middle of my first build. The lower is completed and now I'm getting ready to order the barrel and BCG. Do I need to spend money and buy headspace gauges or go, no-go gauges? I have been told that it's absolutely necessary and then I have been told not to worry about it. I wanna do this right but I have the bank account to think about too... Sadly I don't know anybody that has their own gauges or I could just borrow them and be done with it.
Any info would be appreciated! |
|
Quoted:
I am currently in the middle of my first build. The lower is completed and now I'm getting ready to order the barrel and BCG. Do I need to spend money and buy headspace gauges or go, no-go gauges? I have been told that it's absolutely necessary and then I have been told not to worry about it. I wanna do this right but I have the bank account to think about too... Sadly I don't know anybody that has their own gauges or I could just borrow them and be done with it. Any info would be appreciated! As long as it is from a quality barrel manufacturer like BCM, Spikes, Daniel Defence, Stag, YHM, etc. you should be fine... Normally, the barrels are head-spaced at the factory so buying a Go/No Go gauge set is somewhat overkill...Good Luck. |
| They are not that expensive. It is not all that unusual to find issues when building rifles from various manufacturers of parts. My experience is everyone errors towards the loose side. It is always good to know where the chamber size is. If You do have issues, you will know it is not that, and save you from possible chasing in the wrong direction. I would get a no-go, go and field. You can find them in sets sometimes reasonable. Craig |
|
I'm in the camp that believes checking headspace isn't necessary IF you buy parts from known, respected companies. If it makes you feel good, you only need one gauge, the Colt field gauge, which you can buy from Brownell's. To properly measure head space you should remove the extractor (easy) and the ejector (not so easy unless you have the jig). I have the gauge, but I never use it. On a new build I do the one round in the mag function test. I retrieve the case and inspect it for signs of excessive headspace. If it looks good, I shoot the hell out of it and don't look back. |
|
The Go and No-go gages should be used to check new assemblies to insure they are within spec.
The Field or max chamber gage is used to make sure a weapon that was headspaced correctly when new is not excessively worn. When I check an AR I do not have a history on I determine what the headspace is so I can tell how far from failing the max chamber gage the weapon is. I have not had a new weapon fail the mil No-go gage, but I have had several fail the 1.4640” Go gage. Some gages require extractor and ejector removal for best accuracy. The Forster’s I use do not have relief cuts for either and Forster recommends removal. Go with the manufacturer’s instructions for your brand of gages. |
|
Most people check headspace to confirm safety first and foremost. For that purpose, GO and NO GO are not really needed or useful.
A live round can be substituted for a GO gauge, following all safety protocols, obviously. If you can chamber a live round, then it would pass a GO gauge. A NO GO gauge is an intermediate measurement that doesn't say much about safe headspace. Failing a NO GO gauge still doesn't tell you safe or unsafe. You'd need a bottom end measurement, the FIELD gauge, to determine if the headspace is safe to fire or not. In the end, the FIELD gauge is really all you need for safety. |
|
Quoted:
FYI alot of people keep spreading the myth but its just not true. there is no need to remove the ejector or extractor to check headspace. people will argue til they are blue in the face but check your TM, if it mattered it would say to do it in the TM. That is because the gauges the .Gov uses are rebated to where this is not a problem. 
Follow the gauge manufacturers instructions. 
|
|
In my experience rounds will chamber in weapons that have failed a Go gage.
I am not saying that is universally true, but it has been the case in the ones I have seen. Also the tolerance range for cartridge cases is massive compared to the tolerance for headspace gages. IMO using a live round for a Go gage can be very misleading. The mil-spec No-go gage is the reject point for a new weapon, as a new weapon that fails that gage may have a short service life before failing the max chamber gage. |
| I got my BCG and upper from pretty reliable manufacturers but just to be sure I bought a $30 no-go gauge. I didn't do the go-gauge and figured the no-go gauge should be sufficient for checking. It's really all about how much you want to spend to "be sure". If you're really worried spend the $60 and get both, $30 to get the no-go or just take it to someone to have them checked. I was convinced when it passed the no-go gauge; which is the most important of the two. |
|
Quoted:
FYI alot of people keep spreading the myth but its just not true. there is no need to remove the ejector or extractor to check headspace. people will argue til they are blue in the face but check your TM, if it mattered it would say to do it in the TM. It doesn't say to do that in the TM because the GI gauges are relieved for the ejector... It really doesn't matter unless the gun "almost" closes on a NO GO gauge. Then you have to determine if the resistance you're feeling is the ejector or the gauge. In such a case, you really do need to remove the ejector. That's not a horrible ordeal with the right punch, some patience, and an understanding of how not to launch the ejector into the living room carpet. OP, Forster GO and NO GO gauges for .223 and 5.56 (essentially the same, though the tolerances are slightly different) are in stock at Brownells, and cost about $24 each. |
|
I'd rather be safe then sorry but that's because I'm ocd. Its your rifle so do as you please. However, I bought all 3 forster gauges (Go, No-Go, Field) at Fulton Armory for $80 because they were sold out everywhere else. I already got plenty of beer in return for lending them out to a couple of friends of mine so for me it wasn't such a bad deal
Forster Gauge Set |
AR Sponsor