Calling all 6.5 Creedmoor folks

Majja

Private
Minuteman
Jan 8, 2018
23
9
I am building a 6.5 creedmoor and need some barrel advice. the use of the gun may be abit of hunting both predators and Mule deer, and ringing steel occasionally out to 1k. I was thinking of either a 18 or 20 inch barrel from either Wilson Combat or McGowan. I will be using a AGB for the build.

The way I understand it is with the 6.5 I want as long a dwell time as possible. The dwell time is a product of manipulating the gas flow via, gas port location, buffer spring and buffer is, is that correct?

So what would be best a +2 or +3 in gas system on a Mcgowen in a light or modified contour Barrel. Or the WC 18-20 inch barrel with the std Rifle length system? Or option C ... I am over thinking it ... pick the one I want and just run with it.

Also how do these to barrels stand up against each other.

Thanks all in advance all opinions welcome.
Matt
 
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Whatever barrel you decide I would go with a +2 gas system. I have a standard rifle in a 20 inch 260 and my hunting buddy has the plus 2 in a creed. When or if I change it will be a +2.
 
This topic comes up from time to time. Here's a recent thread that might give you some more info: https://www.snipershide.com/shooting/threads/ar10-barrel-and-gas-system-advice.7033118/#post-8916490

I think you're confusing "dwell time" with gas system length. The "dwell time" starts from the moment the bullet passes the gas system, and ends the moment the bullet leaves the barrel. If you scroll down to the bottom of the page here at AR15Barrels.com, you can see some graphs and tables that show a pressure curve for a .223 load fired from an AR15 platform. It charts the pressure over distance, and marks the pressure at the different gas port locations (Pistol, Carbine, Mid, and Rifle).

Obviously, a 6.5 Creedmoor is different, and due to the way the powder burns, it sustains a higher pressure over a greater distance, which is why you RARELY if ever see 6.5 Creedmoor with Carbine or Midlength gas systems - the pressure is much higher than the AR15 in .223 and causes violent cycling. Due to this high pressure, you'll want the longest gas system that can reliably function. However, if you go TOO long and reduce the dwell time, that can cause issues as well. It's all about trying to find the correct balance.

In simple terms, to tame the pressure in a 6.5 Creedmoor, you can
1. Go with an extended gas system (Rifle +1" or +2")
2. Use an adjustable gas block
3. Use an adjustable carrier
4. Some combination of the above

Lots of people have been reliably shooting 6.5 Creedmoor with 20"+ barrels with Rifle gas systems. This would be roughly comparable to using a Carbine gas system on a 16" barrel or a mid-length gas system on an 18" barrel: a little overgassed, but not detrimental to the function of the system if you have the right components.

My $0.02: Get the best barrel you can afford, and worry about the gas system as a secondary concern. An extended system makes a lot of sense once you get to 20"+, but with an 18-20" barrel the Rifle-length gas will probably be just fine. Just invest in a quality adjustable gas block or adjustable carrier to fine-tune your system.
 
I am not sure...must be if they want that short of barrel
I was looking at the carry ability of the rifle but at this point open to anything. I just dont want t
This topic comes up from time to time. Here's a recent thread that might give you some more info: https://www.snipershide.com/shooting/threads/ar10-barrel-and-gas-system-advice.7033118/#post-8916490

I think you're confusing "dwell time" with gas system length. The "dwell time" starts from the moment the bullet passes the gas system, and ends the moment the bullet leaves the barrel. If you scroll down to the bottom of the page here at AR15Barrels.com, you can see some graphs and tables that show a pressure curve for a .223 load fired from an AR15 platform. It charts the pressure over distance, and marks the pressure at the different gas port locations (Pistol, Carbine, Mid, and Rifle).

Obviously, a 6.5 Creedmoor is different, and due to the way the powder burns, it sustains a higher pressure over a greater distance, which is why you RARELY if ever see 6.5 Creedmoor with Carbine or Midlength gas systems - the pressure is much higher than the AR15 in .223 and causes violent cycling. Due to this high pressure, you'll want the longest gas system that can reliably function. However, if you go TOO long and reduce the dwell time, that can cause issues as well. It's all about trying to find the correct balance.

In simple terms, to tame the pressure in a 6.5 Creedmoor, you can
1. Go with an extended gas system (Rifle +1" or +2")
2. Use an adjustable gas block
3. Use an adjustable carrier
4. Some combination of the above

Lots of people have been reliably shooting 6.5 Creedmoor with 20"+ barrels with Rifle gas systems. This would be roughly comparable to using a Carbine gas system on a 16" barrel or a mid-length gas system on an 18" barrel: a little overgassed, but not detrimental to the function of the system if you have the right components.

My $0.02: Get the best barrel you can afford, and worry about the gas system as a secondary concern. An extended system makes a lot of sense once you get to 20"+, but with an 18-20" barrel the Rifle-length gas will probably be just fine. Just invest in a quality adjustable gas block or adjustable carrier to fine-tune your system.
Thank you for all the great information. I plan on using either a JT or superlative arms adjustable gas block.
 
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Built mine with a Faxon 16" Gunner profile barrel and couldn't be happier. Lots of pigs and coyotes with it from 50 -400m, and recently got my first elk at 315. Have shot steel out to 600m consistently without issues. I prefer shorter barrels as I hunt/shoot with suppressor and prefer the shorter OAL. Carbine length gas system (would do over again with rile if I could, but not sure if can get with that short of a barrel). Runs fine so long as I clean after EVERY outing.
 
running criterion 16” hybrid barrel with rifle length gas block. Superlative arms adjustable gas block, jd industries full mass bcg and bolt. Armalight buffer tube and buffer and spring. Areo precision upper and lower and works perfectly .running suppressed . Running hornaday hunter 143 led-x averaging about 2540 FPS with silencerco hybrid can
 
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