Hello, I am new to AR's & looking for my first.  Where is the overall barrel length measured from the rear on an assembled rifle?  
TIA,
Eric

To get the overall barrel length you see advertised, you have the bolt all the way forward, and you stick a cleaning rod down the barrel until it hits the breechface of the bolt. You do this with removable muzzle attachments off, and measure from the tip of the barrel.

If you are talking about the overall length of the rifle, you measure from the furthest spot on the  stock to the muzzle (without the flash-hider on) and that will give you the overall length of the rifle.

That's probably about as clear as mud, but someone will probably be along shortly with a better description

WIZZO

Thanks for the reply.  I am off to the gun shop tomorrow & hope to come home w/ my first AR.  I was just wanting to double check barrel length myself & not take someones word as law.  With the bolt foreward, how much length does a A2 style birdcage add to the cleaning rod?
Thanks again,
Eric

Almost exactly an inch.

Here's some pics I posted on another thread similar to this.





The overall length is right at 31 inches in legal terms. As you should be able to see in the pic, with the A2 FH, the complete overall length is about 32" so it adds about an inch to length. That is why a 14.5" barrel has to have a FH permanently attached that is at least half an inch longer than the regular A2 to bring it up to 16". Otherwise, you'd have a 15.5" barrel if you permanently attach an A2 FH to a 14.5" barrel.

WIZZO

From tha barrel extension to the muzzle not the end of the flash hider only on 14.5 barrels is it to the end of the hider because they have to be part of the barrel to make the miniumum 16".A 16" barrel with A2 hider is a little over 17".With the hider off its 16.1.Overall legnth of the rifle has to be 30"at a minimum I beleive.31 1/4 is my carbines over all with a permanent phantom on a 14.5 and with the old car stock its an inch shorter.

Quoted: Overall legnth of the rifle has to be 30"at a minimum I beleive.

Minimum OAL is 26" for a rifle, unless you live in one of those odd states that has their own higher minimum length.

-1 for a flourecent green tape measure

Hehehe, I think it was $3 on sale somewhere......Matches my KX 250 dirtbike though

WIZZO

Not a stupid question at all, Boss.

If you are looking for an AR, you will be seeing mostly 16"ers or maybe 16.1"ers. This is the standard carbine configuration, and you won't need a tape measure, as all dealers know the difference.

The other common AR is the 20"er, which is the standard rifle configuration (and is the measure of the venerable M16)

so you will likely be seeing carbines in 16, and rifles in 20

If I could make one recommendation, to would be to highly consider a flat top configuration (A3) since it opens up future options to you that the A2 (permanent carry handle) does not.

welcome to the site, and welcome to AR15's

Hey guys, thanks for the advice.  Brought home my 'first' AR today.
Bushmaster A3 collapsible stock, full 16" M4 type barrel w/ screw-off A2 flash hider.
Just for reference, my measurements are:
total rifle collapsed:32 & 3/8"
barrel from inside w/ FH:17 & 1/2"

Thanks again,
Eric

That is one of the most popular ARs today Eric, and one I am sure you will enjoy.

I cannot recall one problem from Bush M4A3 owners..........To the contrary...they are universally praised.


Good score!!