Before you suspected it is the barrel, did you do a check list for culprits.
1) Make sure front action screw is not touching stock. Take a rat tail file and lightly ream.
2) Make sure magazine box is not binding. Should be able to jiggle it a little.
3) Torque action screws. Torque sequence - Front screw "Farmer" tight, rear screw tight and middle screw snug so it does not fall out.