Anybody know? Sabre has a fluted option but it's not cheep and everything else I'm finding weighs more than 3 lbs. At that weight I would probably be better off with a 20 inch government profile. Twist isn't a major concern, just my ability to carry, stand and deliver.

Rifle or mid length gas? The lightest you are going to get is lightweight (.625 the entire length) or A2 profile (.625 under the handguards .725 after the FSB). Your best bet for rifle length gas is probably buying a 20" and having it cut down. The only mid length option that I know of is this. Most 18" barrels are for SPR rifles, that is why they are all heavy profile.
Dustin

Sabre defense makes a Medium profile, fluted, chrome lined, 4150 CMV barrel that is pretty light weight.

I bought one from PK Firearms a couple years ago. It made a pretty handy well balanced rifle with a DD 12" & Emod.

Get yourself a BCM 20" and send it off to ADCO and have it reprofiled to light wt from the gas block on out to the flash hider...and cut  and threaded at 18"

Keep your FSB at .750 if you like or have it all milled down to .625 and get a lo pro gas block (La Rue tactical comes to mind) & a

Troy TRX Xtreme 13.0 Battlerail (they even come in FDE)



ACDO did this one for me ...left it at 20" though