Long-range AR15 barrel?

[BigPineyTradingPost]

What's a good brand of barrel and length of barrel?
20 inches?
24 inches?
1:7 twist?
Looking at using a 75-grain .223 bullet.

 

[MTRecon]

I'm using a WOA 26" Varmint Upper 1/8.

 

[BigPineyTradingPost]

I'm using a WOA 26" Varmint Upper 1/8.

Didn't think of that length of barrel. I like.

 

[srt-4_uk]

As long a barrel as you can tolerate
1-7 or 1-8, wont really matter with 75gr
Any barrel that gets recommended every time someone says "which brand barrel do I get" will do fine

 

[Kickin45]

Each inch of barrel on a 223 gas gun equates to roughly 25fps above 16” length.
Twist for your intended purpose and projectile weight is more important.
as a general rule, anything above 18” on a gasser delivers very minimal improvements.
The military uses a 20” on their sniper that is good to 800yds.