Where is the best place to buy the heaqdspace tools for a 5.56 AR? Do I only need the field, or should I get the go and no/go as well?
Nevermine, search is your friend:D:rolleyes:.
Bushmaster sells a real 5.56 headspace “Field” gage. Also, BillRicca.com may have some of the real USGI ones as well.
Brownell,s sells foster,s no,go and field. :o
And those gages are generally incorrect for a true 5.56 chambered weapon.
good to know,
thankyou Iraqgunz
IG turned me on to Bill Ricca. Good guy with GI gauges, if any are left.
Thanks bro, I went with the Bushmaster 5.56 “Field” gage. One question, do you have to remove the ejector/extractor to get the correct reading? Or are you good to go with those in the bolt?
The gauges on the BM site look a lot like Forster gauges. They will require removing the extractor, probably not the ejector. I’ve used both the USGI from Bill Ricca and Forster, I prefer the USGI from Ricca.
I like the ones from Bill as well. Easy to use and he’s a nice guy to deal with.
Generally speaking you will need to remove the extractor to check it. You can leave it in place, but over time it will cause wear on the rim of the gage. That is one reason the original GI ones are better.
Hey IG,
Just thought I would ask. Is this one appropriate for 5.56 chambers? It seems to be correct. It says it’s “Colt spec” and doesn’t show whether it’s a field or USGI.
http://www.brownells.com/.aspx/pid=6646/Product/5_56mm___223__HEADSPACE_GAUGE
Thanks for any input from anybody!
If you bought a complete rifle from a reputable manufacturer, what problem could you possibly solve with a chamber gauge?
Unless you own a machine shop full of high dollar tools, there is nothing you can do with any information provided to you by head space gauges. Online “gunsmith” retailers and other outlets have made big bucks selling worthless tools to woodshed gunsmiths.
Spend your hard earned money on something more valuable!
Here is a link to a PDF on the Brownells gauge. It sounds like a true 5.56 field gauge.
http://www.brownells.com/userdocs/learn/Inst-300%20Colt%20HS%20Gauge.pdf
Proper headspace is of critical importance for the safe and proper functioning
of the Colt AR-15/M16 rifle. Insufficient headspace can prevent
proper bolt lockup while excessive headspace may lead to cartridge case
separations or misfires. In most gunsmith shops, commercial gauges are
used which are generally made to SAAMI or industry standard and are normally
suitable for checking most sporting firearms. However, for measuring
the maximum acceptable headspace on the AR-15/M16, those gauges may
not be entirely suitable since Colt utilizes a special “Field” gauge that is
slightly different from most commercial “Field” gauges.
Colt factory specifications call for a “Field” gauge that is 1.4736". The
Brownell AR-15/M16 Headspace Gauge is precision-ground specifically to
match the Colt “Field” gauge dimensions and can be used with confidence
when checking Colt manufactured AR-15/M16’s.HOW TO USE
Proper use of this gauge is absolutely critical. Improper use can lead to
inaccurate measurements, causing an unsafe rifle to be fixed, with great
potential for injury to the shooter.
Follow the manufacturer’s recommended procedure and remove the Bolt
Carrier Assembly from the Upper Receiver. Strip the Bolt after removing it
from the Bolt Carrier. By removing the Extractor and Ejector, you prevent
the possibility of a false reading, caused by pressure or tension from these
components on the Headspace Gauge. In addition, the amount of force required
to cam the Bolt into the locked position is greatly diminished. This
is especially important in situations where the Bolt will barely close on a
headspace gauge. If the Extractor and Ejector are present, they can prevent
the bolt from closing on the headspace gauge.
After the Bolt is properly stripped, the Bolt face should be cleaned to
remove any dirt, carbon or foreign material that can cause a false reading.
The chamber should also be inspected and thoroughly cleaned. Finally, the
Headspace Gauge itself should be checked and any oil or grease removed.
Reinstall the Bolt Carrier with the stripped Bolt in place and position
the Bolt far enough to the rear to allow the insertion of the Headspace
Gauge into the chamber. Place the Headspace Gauge in the chamber, then
GENTLY, CAREFULLY, move the Bolt Assembly forward. DO NOT SLAM
THE BOLT CARRIER FORWARD! EXCESSIVE FORCE WILL RUIN THE
HEADSPACE GAUGE AND MAY DAMAGE THE CHAMBER! Use only
your thumb and forefinger to move the Bolt Assembly forward. If headspace
is excessive, the Bolt WILL cam into position and the Bolt Carrier will move
forward so that its rear is flush with the rear of the Upper Receiver. If the bolt
DOES NOT cam into the locked position, the rifle does not have excessive
headspace. Remember, the Bolt should NOT close on a field gauge.Please note that when checking headspace, the AR-15/M16 should ALWAYS
be held in a normal horizontal position. DO NOT turn the rifle upside
down as the Cam Pin may slide out of position and prevent retraction of the
Bolt Carrier.
While not absolutely necessary, we suggest separating the Upper and
Lower Receiver units. Doing so makes checking and cleaning the chamber
and use of the Headspace Gauge easier.
After checking the Headspace, reinstall the Extractor and Ejector into
the Bolt. Reassemble the firearm according to the manufacturer’s instructions.
Check for proper functioning using ACTION PROVING DUMMIES.
Make sure ALL SAFETY MECHANISMS are fully functional as designed
and approved by the manufacturer. If these tests prove satisfactory, test-fire
the firearm with live ammunition in a SAFE and APPROPRIATE manner.
IMPORTANT! If the firearm is a fully or semi-automatic design, start the live
ammunition tests by first loading an ACTION PROVING DUMMY, then a
live round, into the magazine. Only after several tests have been conducted
in this manner should additional rounds be placed in the magazine and
fired.
IMPORTANT NOTE: We cannot emphasize too strongly the importance
of correct headspace. Excessive headspace can, under some conditions, cause
damage to the firearm and/or injury to the user of the rifle.
Yes if you bought a rifle from a reputable manufacture then you don’t need one. If however you build one then it’s a good idea to check the head space.
The info you get from the gauge will tell you if your rifle is safe to shoot.
I bought 5.56 Nato gauges directly from Forster on their website. They sell .223 and 5.56 versions, but Midway and Brownell’s only seem to carry the .223 versions.
Brownell’s does sell Clymer 5.56 gauges, though.
I bought them because I bought spare bolts for both of my AR’s - I store the spare bolts along with a spare firing pin in Magpul grip cores.
I wanted to make sure that my replacement bolts were properly matched to the barrels in my AR’s. I found that one bolt is too tight in one barrel (won’t close on “GO”), while the other is a a bit tight but will close. The other bolt is fine with the other barrel. It does hurt to make sure your spare parts won’t result in an unsafe condition, given manufacturing tolerances. I wouldn’t just drop any bolt into any barrel without checking it.
So is the gauge from Brownells a good gauge? Or should I look at Forster?
Spend away junior…
Gee thanks grandpa.
I will be sure to email Colt and FN and tell them that they are wasting there time checking headspace.
Thanks for the link, 5pins.
Actually I already have and use that gauge, and I trust it. I was interested in IG’s opinion of it.
All that info is what comes with the gauge.
As far as mk18pilot, sorry pal. You have a right to your own opinion, but not your own facts. Stating flatly “there is nothing you can do with any information provided to you by head space gauges.” is completely wrong. If you CHOOSE to not to use a certain gauge or tooling for your self, that’s your own choice. I’ll be sure to never fire a rifle you built. But using that gauge for it’s intended purpose (replacing bolts, re-barreling, etc.) is entirely appropriate.
Checking headspace on frequently used rifles is a good idea for annual maintenance. I look at money for a USGI field gauge as cheap insurance to keep my rifles running. YMMV.