I can give you my limited experience with nitriding. I had 3 6mm barrels made. They were made back to back to back from the same lot of steel. I chambered them all in 6brx. They were the straightest barrels you will ever see. The two that were not nitrided shot under .25" at 200 yards consistantly. One shot a 200 19x at 600 yard fclass which is a national record, and the other shot a 1600 120x at a 600 yard fclass match. That match was out of 1600 so it didn't drop a point all weekend. I got the nitrided barrel back and cleaned it for hours. Looked in it with the borescope every 20-50 strokes or so til it looked clean. I used iosso to polish it up after cleaning with a liquid solvent to get most of the gunk out as that was the instructions from guys with more experience nitriding than me. I cant get it to shoot under .5 inch at 100 yards consistently. I tried 1.5 gr diff in powder and .005 off the lands to .050 off the lands. Ive given up on it and will not nitride any more of the barrels I receive. Barrels are expendable so Ive decided I will just shoot untreated barrels as Ive never had one from my maker that won't shoot a 1" group at 600 yards, except for the nitrided barrel. Take my experience for what its worth.