Barrel length and velocity question

[bob332]

I was wondering what was the shortest barrel for the 6.5Creedmoor that will RELIABLY keep a ~140-150 projectile moving at 1200fps (with a cushion) to ~1200yds at sea level?
Bullet will be a quality match (Lapua, Hornady, Sierra or one of the all Cu units) bullet.
Barrel will be a quality unit - Krieger, Lilja, etc.
Again, looking for the shortest length barrel that will accomplish this on a reliable basis in order to keep weight down.
Firearm will be a something similar to a DPMS GEN II, so I can use some AR15 parts in the lower (if I can ever find a stripped lower, if not I will buy a complete one in .308 and swap out the barrel and other essential parts). My reason for going with the shortest barrel is I really do not see me shooting farther and if I did I could just change barrels or buy a quality bolt rifle, plus, from what I have read you are not going much further than the range I have wanted to build for - IF THIS STATEMENT IS NOT ACCURATE PLEASE LET ME KNOW. Also, my first choice would be something in the DPNS GEN II family.
Will be using an Adj Gas Block setup.
The rest of the firearm will have the necessary parts to accomplish this feat.
Also, not sure how much ambient temp is a factor, but I would say the coolest would be ~30F going up to ~100F.
I will start with quality boxed ammo but plan to eventually load my own, so you can assume these will be handloaded.
Thanks in advance for your time and knowledge.
Bob

 

[brazz04]

16" is probably the shortest that would work. With a 2400 fps muzzle velocity using the Hornady 147 Match, I get 1218fps at 1200 yards using the Ballistic AE app. Based on looking at others velocity numbers around the interweb, 2400fps at the muzzle with a 147 grain bullet should be a fairly accurate velocity estimation and maybe even a bit conservative.

 

[bob332]

Thank you for your reply. This is at sea level? And if I were to go 18" would be a safe 'insurance policy' should any take care of any 'gremlins' one may encounter?

Do you recall what brand barrel this test was done using? Or is it just simply math?

Thanks in advance,
Bob

 

[brazz04]

Thank you for your reply. This is at sea level? And if I were to go 18" would be a safe 'insurance policy' should any take care of any 'gremlins' one may encounter
Do you recall what brand barrel this test was done using? Or is it just simply math?

Thanks in advance,
Bob

I just did some searches on what velocities people were getting out of 16" barrels.

This is the one that is referenced most often.
https://rifleshooter.com/2016/02/6-...el-length-on-velocity-cutting-up-a-creedmoor/

Here's a thread talking about shorter barreled Creeds.
https://www.snipershide.com/shooting/threads/short-barrel-6-5creed.6564163/

I stumbled on your question because I'm looking to go with a 14.5" barrel that is pinned to 16" on my Remington 700 so I have been doing a lot of research on it lately. It's hard to find any velocity numbers on a 14.5" I've found.

 

[Lapuapalooza]

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[_Windrider_]

I wouldn’t go any shorter than 20 and a rifle length +1 gas system.