The Firearms Forum banner

1 - 20 of 22 Posts

·
Registered
Joined
·
58 Posts
Discussion Starter #1
Hello all. Hope all is well with you and your families. I need help; what would be the ideal barrel twist for a 24” 6.5 creedmoor barrel in or 308 platform? Also, what would be the ideal gas system size for this barrel and finally, is a heavy buffer tube necessary for this barrel? Any help will do thank you.
 

·
Registered
Joined
·
420 Posts
Creedmoor’s usually have a 1-8 twist, for a 24” barrel, I’d expect a rifle length + 2”, would work the best.

I built one with a 22” Odin Works barrel, and it shot 1/2” groups right out of the box.

For a buffer tube, I like to keep it simple and go with a buffer tube kit that is designed for AR-10’s or 308. Very often people like to customize this part, then their gun doesn’t cycle right, and they get confused with different springs, buffer weights, etc. Keep it simple and it will work great.

I do recommend an adjustable gas block, I’m in the process of changing out all of my AR’s to an adjustable GB, the brass ejection pattern is very random out of my AR-10’s. Odin works makes a “Tunable gas block” that runs for around $55.

Good luck!
 

·
Registered
Joined
·
58 Posts
Discussion Starter #3
Creedmoor’s usually have a 1-8 twist, for a 24” barrel, I’d expect a rifle length + 2”, would work the best.

I built one with a 22” Odin Works barrel, and it shot 1/2” groups right out of the box.

For a buffer tube, I like to keep it simple and go with a buffer tube kit that is designed for AR-10’s or 308. Very often people like to customize this part, then their gun doesn’t cycle right, and they get confused with different springs, buffer weights, etc. Keep it simple and it will work great.

I do recommend an adjustable gas block, I’m in the process of changing out all of my AR’s to an adjustable GB, the brass ejection pattern is very random out of my AR-10’s. Odin works makes a “Tunable gas block” that runs for around $55.

Good luck!
Hey! Thank you for the info. I receive that keep it simple advise, along with everything else you said. Question; when using a rifle length gas system plus 2”, do I have to make an additional hole somewhere?
 

·
Registered
Joined
·
58 Posts
Discussion Starter #5
No sir, the barrel will have the gas hole predrilled.
Hello! Hope all is well with you and your family. Thank you so much for this enlightenment. However, since I won’t have to move the block down a couple of inches, where does the extra 2” of tube go? Thank you.
 

·
Registered
Joined
·
58 Posts
Discussion Starter #6
Hello! Hope all is well with you and your family. Thank you so much for this enlightenment. However, since I won’t have to move the block down a couple of inches, where does the extra 2” of tube go? Thank you.
P.S. when you say that the barrel will already have a bored hole for the gas block, you are speaking of the regular hole that barrels have for gas systems, right? Thank you.
 

·
Super Moderator
Joined
·
39,828 Posts
John, there are three different lengths of AR gas tubes - (1) pistol length, (2) carbine length, and (3) rifle length. One of those lengths will fit your rifle, if you are building an AR type rifle. As far as having 2 inches left over, you know that your tube has to be long enough to go into the upper receiver to match up with the "key" on the bolt carrier group, which is actually about two inches inside the receiver.
 

·
Registered
Joined
·
58 Posts
Discussion Starter #8
John, there are three different lengths of AR gas tubes - (1) pistol length, (2) carbine length, and (3) rifle length. One of those lengths will fit your rifle, if you are building an AR type rifle. As far as having 2 inches left over, you know that your tube has to be long enough to go into the upper receiver to match up with the "key" on the bolt carrier group, which is actually about two inches inside the receiver.
Hello gdmoody. Hope all is well. The barrel I have is a 24” creedmoor barrel (LR 308 platform). Iv read they should have a rifle length + 2” gas system because they’re long barrels. Please advise. Thank you.
 

·
Super Moderator
Joined
·
39,828 Posts
The only ones I have built are .300 Blackout, 5.56 ,or 7.62X39 rifles and the longest barrel I have used is 20 inch. If you have the barrel and the gas tube just put the suckers together and see if the tube is long enough. No offense intended but it ain't brain surgery.
 

·
Registered
Joined
·
58 Posts
Discussion Starter #10
The only ones I have built are .300 Blackout, 5.56 ,or 7.62X39 rifles and the longest barrel I have used is 20 inch. If you have the barrel and the gas tube just put the suckers together and see if the tube is long enough. No offense intended but it ain't brain surgery.
Okay. I was hoping you would say that. Thank you. It’s just when I googled that question, different forums came up with this theory that having a long barrel requires a longer gas system. But what you said just makes sense. And it wasn’t taken offensively. I appreciate you and your help.
 

·
Administrator
Joined
·
11,869 Posts
I put a 24" barrel on an LR308 I built and used a rifle length gas tube. No problem.
 

·
Super Moderator
Joined
·
26,796 Posts
Whatever barrel you buy will be drilled with a gas port and you have to use whatever length tube the barrel maker has it drilled for. Bit a little difficult to get an AR to cycle if you used a carbine length tube in a rifle length barrel. Just like it would be impossible, without cutting to fit a rifle tube in a carbine.
 

·
Registered
Joined
·
58 Posts
Discussion Starter #14 (Edited by Moderator)
Whatever barrel you buy will be drilled with a gas port and you have to use whatever length tube the barrel maker has it drilled for. Bit a little difficult to get an AR to cycle if you used a carbine length tube in a rifle length barrel. Just like it would be impossible, without cutting to fit a rifle tube in a carbine.
Hello howlnmad. Thank you for your advice. I understand what you’re saying and see it that way. I’m just not familiar with nor see the necessity of the theory of installing a rifle length + 2” gas system on a 24” 6.5 creedmoor barrel. Yet people are saying that. Thank you.
 

·
Super Moderator
Joined
·
39,828 Posts
Excuse me John, there is no such thing as a "Rifle length + 2" gas tube" You only get the choice of the three lengths I mentioned yesterday.
 

·
Registered
Joined
·
58 Posts
Discussion Starter #16
Excuse me John, there is no such thing as a "Rifle length + 2" gas tube" You only get the choice of the three lengths I mentioned yesterday.
Hey gdmoody. Okay, thank you. But choosing the extra length gas tube is up to the individual, but not truly necessary is it? And if it is, do you know where I can see an instructional installation video? Because there’s non on YouTube. Thank you.
 

·
Super Moderator
Joined
·
26,796 Posts
Excuse me John, there is no such thing as a "Rifle length + 2" gas tube" You only get the choice of the three lengths I mentioned yesterday.
It looks like we're both learning something new. Apparently, there is. I didn't read through the site enough to see if you have to order a barrel through them, but they are available.
 

·
Super Moderator
Joined
·
39,828 Posts
OMG and there are rifle +1 and rifle +3 also. I have to apologize to you John. I had no idea!! That's what I get for not building an AR-10.
 

·
Super Moderator
Joined
·
26,796 Posts
You're not alone George.
 
1 - 20 of 22 Posts
Top