Longer barrel, accurate - 6mm ARC upper

[Stonegables]

My first 6mm ARC is built around a Sanders Armory 20" upper. I have only shot 6 boxes of ammo so far. All five shot groups sub MOA except for shooter error.

Looking quite interesting to me.  if one is liking the 20" barrel - why not 24" for another 110 FPS or so?

Thank you!

I have three AR style rifles with 20" bbls. A DD5V5 in 6.5 Creedmoor that DD says will shoot 1000M accurately, A 25-45 Sharps, and the above referenced 6mm ARC. They all have somewhat heavy bbls. and are at the upper limit for weight and portability for me, a 71 year old curmudgeon with a metal and polymer right shoulder. I think if I was going longer than 20", I would just go for a bolt action or single shot.