Bench or fielding it?
If you're hunting out in the field with it. Light, but don't expect to shoot a lot of rounds before your groups will start to open up.
1000 yards? Heavy barrel 24", leave it on the bench kuz it ain't gonna be much fun to hump around.
Ar15performance.com has a 18" .264 LBC (6.5 Grendel variant) for a very reasonable price plus you can have it melonited.
Black hole weaponry also makes a variety of barrels that you can have totally customized right down to size of the gas port. Custom fluting and finishes. They have a stellar rep for service and quality. Only bad thing is you have to wait up to 2 months.
Assumption is the mother of all ****ups.
Know what you know, Know what you don't know. -Paul Pedzolt
"Jack of all trades, master of none, though oftentimes better than master of one" -Mynshul