I have a NULA 20. I purchased from another member on the website. It was in 6.5X47 Lapua. It did not shoot consistently. I Borescoped the barrel. It was extremely rough.
It is currently being rebarreled to 6.5 Creedmoor.
Bartlein Barrel 8 twist (for Berger 140's) Harrels Mini Muzzle Brake.
Should be done in next couple of weeks.
I have had several 6.5 CMs. All have shot one ragged hole.