barrel extention

[jh1]

I noticed some co. sell barrel extentions.What's their purpose ,do I need one,or want one? Yes i know they make the barrel longer,right?

[markm]

You need one!

[jh1]

You need one!

Why?What's for?

[markm]

It's where the bolt locks into battery just behind the chamber. Without it, the AR wouldn't work. (I'm going out on a limb and assuming we're talking about the AR platform ) If you own an AR, you already have a barrel extension.... There's no need to buy an additional one, because you can't cowitness them.

[jh1]

It's where the bolt locks into battery just behind the chamber. Without it, the AR wouldn't work. (I'm going out on a limb and assuming we're talking about the AR platform ) If you own an AR, you already have a barrel extension.... There's no need to buy an additional one, because you can't cowitness them.

Yes talking ar. Building my first.Barrel is 18" from noveske,on its way here. thank you.

[markm]

Yes talking ar. Building my first.Barrel is 18" from noveske,on its way here. thank you.

The barrel you ordered will have the extension already installed. I believe the extension is mated to the barrel before the gas port is drilled. I.E. the port/Front sight base is TDC'd in relation to where the extension ends up on the barrel.

[TheGhostRider]

The barrel you ordered will have the extension already installed. I believe the extension is mated to the barrel before the gas port is drilled. I.E. the port/Front sight base is TDC'd in relation to where the extension ends up on the barrel.

You are correct Sir!
Of course you already know that....

Regarding barrel extensions: Don't bother buying one unless you are turning your own barrels from scratch.

The extension is installed then pinned in place once head space is established, once pinned the the barrel is indexed so that top dead center of the barrel is ready for the the gas port drilling.
Once the gas hole is drilled the whole assembly is set into a jig so that the front sight assembly can be installed.

Trying to change out barrel extensions on a barrel that is already drilled for the gas port is folly. Finding a barrel extension that properly indexes for head space and lines up with the gas port is virtually impossible.

[jh1]

You are correct Sir!
Of course you already know that....

Regarding barrel extensions: Don't bother buying one unless you are turning your own barrels from scratch.

The extension is installed then pinned in place once head space is established, once pinned the the barrel is indexed so that top dead center of the barrel is ready for the the gas port drilling.
Once the gas hole is drilled the whole assembly is set into a jig so that the front sight assembly can be installed.

Trying to change out barrel extensions on a barrel that is already drilled for the gas port is folly. Finding a barrel extension that properly indexes for head space and lines up with the gas port is virtually impossible.

thanks i guess thats what i wanted to know.