sorry, I've been inattentive to this site
That's a 24" chrome moly MGM with custom engraving 1:8" twist
I call it my 'Freedom barrel', she shoots good too! ... with H380, no less!
I have zero experience with the 6.5 Grendel, but I really like the 6.8 SPC. I have two ARs in that caliber and they are my “go to” hog rifles. I used to have a day and night gun, but since I put a digital scope on my night gun it’s now a day or night gun. Both of them shoot Federal Fusion 115 grain bullets very well. I’ve also killed a few axis does with them as well as a ton of hogs. That little 115 grain bullet will drop a 250 pound hog in his tracks with a high shoulder shot !