checking head space

[Matt.Cross]

Here's my wild shot in the dark, feel free to reality-check my hypothesizing...

It's a little bit of lathe work on either side of 'not good'. If the chamber is 'short', it may be feasible to simply have it re-reamed at the correct depth. If the chamber is 'deep', material would have to be removed from the back of the barrel to 'shortify' the chamber, this would probably also involve re-cutting the recesses for the extractor & whatever more.

[TacBlade]

But, I have heard if you have a chrome lined barrel, you are screwed!!!

[Matt.Cross]

But, I have heard if you have a chrome lined barrel, you are screwed!!!

That may well be true, I don't know. I need to check and see if they make carbide chamber reamers....

[Turbotezza]

I'm not saying it can't be done, but AR barrels have the extension pinned to the barrel so it's probably be easier/cheaper just to buy a new one.

.... If the chamber is 'deep', material would have to be removed from the back of the barrel to 'shortify' the chamber, this would probably also involve re-cutting the recesses for the extractor & whatever more.

[98Z5V]

So how many of you guys have ever checked headspace on an AR platform and it was not correct?

I check every build, and I got lucky on the .308 build.  I don't have .308 gauges, but right when I finished it all up, a .308 owner on ARFCOM offered up gauges for free use.  He's on here as Cabinetman - Rome, thank you again.  <thumbsup>  I was the first one to take him up on the offer, and the gauges were then sent all over the US, to more than 25 members if I remember right.  On that one, when I had the gauges, I checked the new .308 semi build, and my old .308 bolt gun.  Glad I had them. 

Shooting a new factory gun for the first time is one thing - pulling the trigger the first time on a self-build, not hitting it with gauges first - it's a little bit of pucker factor.  You hope (and pray) everything is gonna go right, and it usually does.  What if it didn't that time, though?  :o

[Matt.Cross]

Shooting a new factory gun for the first time is one thing - pulling the trigger the first time on a self-build, not hitting it with gauges first - it's a little bit of pucker factor.  You hope (and pray) everything is gonna go right, and it usually does.  What if it didn't that time, though?  :o

Well, in that case you might be the unlucky recipient of several pounds of high velocity shrapnel, which is good reason to have or borrow a set of gauges. Even worse, you might have a bad chamber that holds up for the first several rounds, and blows up the instant you let someone else shoot it. That's something I couldn't really live with.

[survivalshop]

You have to understand its just not the alignment pin or how much you would have to turn off or what shim . Its the gas port also . All have to be correct to make a barrel .

You can reset the pin , weld holes & reset all, but its a big job & $$.

If your barrel is not head spacing correctly , send it back to the barrel manufacturer with your bolt , some time's you can take a little off the boltface or find a burr on the extension locking lugs OR bolt locking lugs .

As said above , I have not seen one with bad head space ,not that it can't happen , but all those barrels being made , are tested (head space )after assembly . Only after passing ,are  the pin & gas port finished

Since you are the builder , you have to check head space .For your own good.