No I didn't get the 5-R rifling. Before I ordered it the Krieger rep said they haven't noticed any accuracy improvements compared to the 5-R rifling. I have a Krieger (not a 5-R) on a 7 STW that shoots incredible. I haven't shot my 264 yet. Also trying to decide on a scope. I'm mostly using it for hunting and some long range practice.
Krieger told me the same thing. I think he left it with, "but they do seem to clean up easier." That said, I don't care. I wish all the barrel makers offered a canted or Russian style lands, especially Hart. I prefer them and it's not because I expect more velocity or more accuracy but because IME they don't foul as much and clean substantially better and quicker.
Reason I'd like to try that 5-R has more to do with the edges of the rifling being lapped & essentially duller/gentler on the jacketing.. thin jacketed bullets like the Berger namely, have a tendency to tear apart at velocities over (+/-) 3275fps and literally dynomite in flight before reaching the target. I had the 168's over 3300 through my lazz-firebird and was lucky to see 1 shot in 3 get to my paper. Tuned it just under 3200 and it's perfect.. problem went away. And I HAVE talked to others confirming the same issue. The 5-R isn't available in 7mm, for that particular rifle, but in 6.5 it is. I would be curious to see what a longer barrelled 264 could do far as velocities go and VLD's.. In my opinion, I would imagine the gentler 5-R rifling might be te ticket to allowing velocities above 3275 be reached reliably with the Bergers.. 264 is one calibre that could probably do it**