Proof CF 20" or 22" 6.5 Creedmoor for AR Build?

[USNIGHTGUNNER]

I'm in the planning stages for a 6.5 Creedmoor build, and I'm looking to use a Seekins SP-10 kit with either a 20" or 22" Proof CF barrel. It seems like there is minimal velocity loss between a 20" and 22" barrel, and I'm looking for some recommendations on which length is optimum in an AR platform to be able to constantly reach out to 1000 yards. I'm sure all 6.5 barrel lengths can do it effectively, but there must a sweet spot in terms of length?

 

[DavidAR10]

Your choice. Frank nails it @ 1200yds with an 18" pipe. He also had to deal with a ton of wind. Yeah, Frank is good.
I went 24" because, well hell, take the velocity loss from 26" and I didn't like what I saw with 20" without a suppressor.
AND I like the extra optical 4 inches without shaving moar off.
Best to you.

 

[DavidAR10]

How did I forget this?

 

[Stavey]

20” works great for me .

 

[deersniper]

I went with 20”. Would have use 18” if they had one.

How far do you plan on shooting regularly and are you running a silencer ?

 

[USNIGHTGUNNER]

I went with 20”. Would have use 18” if they had one.

How far do you plan on shooting regularly and are you running a silencer ?

500-1000 yards and I will run it suppressed and unsuppressed at times

 

[USNIGHTGUNNER]

I went with 20”. Would have use 18” if they had one.

How far do you plan on shooting regularly and are you running a silencer ?

I'm assuming you like your 20"?

 

[deersniper]

Still waiting for the 20 to get here lol

I have a 18 and a 24 for my AI and use the 18 the most but I shoot 100 percent suppressed.

I wouldn’t go longer than 20 I’d shooting suppressed. It gets to be like handling a skeet gun

 

[USNIGHTGUNNER]

Sounds like the 20” is the ticket. Thanks for the input.

 

[show_boat]

I went with 22 inch with both 308 and 6.5 Creedmoor and have been very pleased

 

[USNIGHTGUNNER]

I'm going to roll with the 20"

 

[Broncovan]

I'm going to roll with the 20"

Don't run the JP LMOS BCG with the 20" proof camgas system. You'll need a standard weight BCG for that length and barrel unless you want to open the gas port up

 

[roamin]

It's around 22fps per inch of barrel loss on anything between 16"-26". So for round numbers 20" to 22" is going to be a 50fps loss which incidentally with 6.5cm equates to a 50 yard loss on all of your performance parameters. Meaning that if your 20" at XXX amount of yards or produces YYY ft/lbs of energy and YY inches of wind drift and YYY inches of drop the 22" would produce nearly the exact same numbers at 50 yards further. Same thing with group sizes at distance the 22" will hold the same group sizes as a 20" 50 yards further as well.

 

[USNIGHTGUNNER]

Don't run the JP LMOS BCG with the 20" proof camgas system. You'll need a standard weight BCG for that length and barrel unless you want to open the gas port up

The guys at JP recommend their VMOS BCG.

 

[USNIGHTGUNNER]

It's around 22fps per inch of barrel loss on anything between 16"-26". So for round numbers 20" to 22" is going to be a 50fps loss which incidentally with 6.5cm equates to a 50 yard loss on all of your performance parameters. Meaning that if your 20" at XXX amount of yards or produces YYY ft/lbs of energy and YY inches of wind drift and YYY inches of drop the 22" would produce nearly the exact same numbers at 50 yards further. Same thing with group sizes at distance the 22" will hold the same group sizes as a 20" 50 yards further as well.

That's a perfect way to interpret the different barrel velocities into real world data. 50fps doesn't sound like a lot, but this explanation provides a more complete picture. Thanks

 

[DavidAR10]

That's a perfect way to interpret the different barrel velocities into real world data. 50fps doesn't sound like a lot, but this explanation provides a more complete picture. Thanks

Doesn't take the integral f(x) by separation of parts to know
that I would gaff off that rule of foreskin in 6.5CM.

I would find the 142gr sweet spot, cut 2" off and stick it in her can
for no loss or even added velocity.

BUTT!!! That's just vulgar me.

 

[Broncovan]

The guys at JP recommend their VMOS BCG.

Yeah, I'm sure they did. Lol
At $500-$560 for the BCG I'd recommend that too ?
After a lot of troubleshooting my LMOS BCG, swapping BCGs, buffers, springs, running the adjustable gas block up and down and 3 different types of factory ammo, I tried a regular ol' PSA full mass carrier and was able to get it adjusted in a few rounds.

 

[USP45]

I just ordered the 22" Proof CF for mine. Will be running nearly 100% suppressed, but not really making it to be a carry rifle so the extra length is ok.

Now if you want long, my 7-300WM with a 29" Krieger barrel and a Saker 762 on the end of that... now you are talking about taking up some space lol. Rifle without the suppressor is 49.5".