You are Unregistered, please register to use all of the features of!    
Firearm & Gun Forum - > Long Guns > General Rifle Discussion >

New bolt carrier group = check headspace?

LinkBack Thread Tools Display Modes
Old 12-15-2008, 10:36 AM   #1
Feedback Score: 0 reviews
infotech's Avatar
Join Date: Oct 2008
Posts: 85
Default New bolt carrier group = check headspace?

On my ongoing AR15 build the complete upper I purchased came with a stock BCG. I purchased one of the custom M16 BCGs from Spikes Tactical and it seems to function just fine -but- I'm reading I need to pull the extractor and check the rifle with a set of go / no go headspace gauges now.

Is this true? Is it something that has to be done every time you replace part of or the entire BCG?
‘‘War clouds were gathering rapidly. The sending of more than 3,000 British army regulars under Maj. Gen. Thomas Gage to Boston further exacerbated the imperial rift. When a column of these troops under Lt. Col. Francis Smith moved into the countryside to collect arms and munitions gathered by the patriot militia, hostilities erupted at Lexington and Concord on Apr. 19, 1775.’’ - The American Revolution Begins
infotech is offline  
Reply With Quote

Join Today - It's Free!

Are you a firearms enthusiast? Then we hope you will join the community. You will gain access to post, create threads, private message, upload images, join groups and more.

Firearms Talk is owned and operated by fellow firearms enthusiasts. We strive to offer a non-commercial community to learn and share information.

Join Today! - Click Here

Old 12-15-2008, 04:30 PM   #2
Feedback Score: 0 reviews
Join Date: Mar 2008
Location: I see you, and you will not know when I will strike
Posts: 24,301
Liked 3517 Times on 1622 Posts
Likes Given: 3590


Is it absolutely necessary? No. With this day and age of CNC Machining and tighter tolerances, you are PROBABLY fine.

That said, in our shop, we do a Go/No Go headspace check for free - it takes about 2 minutes and then you know you are good to go.

Safety first is always the best practice in my mind.

Some have suggested using a dummy round from a previous batch of ammo you had successfully fired. Actually, someone suggested first using a live round, then later a dummy round. You can do that, it's not for me personally - but I suppose it would work in a pinch. I don't believe you have any old ammo that you successfully fired through the weapon, since it's a new build, so a headspace guage would be worth the limited investment if you like to tinker and perhaps build a few more yourself.

You can get the basic one from Brownells for about $20 shipped to your door.

Or you can get the set, which is about $40 to $50 depending on where you shop. If you are going to build/tinker one or two rifles, and leave them alone, it's probably not worth the money. However, if you plan on doing some major kind of work, or building a gun for someone else, it might be worth it to you.

I would own one as part of my standard range kit, but we have them in the shop that I can use for free.

Dillinger is offline  
Reply With Quote
Old 12-26-2008, 04:27 PM   #3
Feedback Score: 0 reviews
stalkingbear's Avatar
Join Date: Sep 2007
Location: Lebanon,Ky
Posts: 4,074
Liked 464 Times on 269 Posts
Likes Given: 229


If you don't have access to headspace gauges and it shoots fine, continue to shoot & have fun. Ars are designed to accept all same standard dimentions bolt carrier/bolt interchangability, and do not require timing. If it's radically different or different sized, then it would be good idea to check headspace.
stalkingbear is offline  
Reply With Quote

Thread Tools
Display Modes

Similar Threads
Thread Thread Starter Firearms Forum Replies Last Post
Mauser Bolt Problem-Please help, bolt does not go back in! vikingxj General Rifle Discussion 15 11-27-2012 09:00 PM
HELP with headspace on 45 acp tsxshooter Semi-Auto Handguns 1 03-27-2009 11:19 PM
Check out this group. skullcrusher Politics, Religion and Controversy 3 03-08-2009 06:18 PM
Critical Headspace RL357Mag General Rifle Discussion 0 07-21-2008 02:38 AM