I have had my .30 Herrett for about a year or so, and I never thought to check it for ROT or 6 vs 8 grooves. I just checked it and it is 1:14 and a 6 groove. The only thing I was aware of to worry about is the possible long throat issue, and mine doesn't have that. It is the 10" version, and shoots great. One ragged hole at 25, and usually about 2" at 100yds, but that is mostly me as the gun has given me the occassional .75" 100yd group. And this is all with 150gr cast bullets. I have played with cast ranging from 90gr to 180grs, but the 150gr has been giving me the most consistent performance and shoots better in this gun than I do, so I might as well stick with it. I can't speak for jacketed performance, but if yours shoots as well as mine, I'm betting you'll be a happy man. I haven't hunted meat with mine yet, just paper, but I'm betting it will work great once I get a chance to hunt with it too.