Re: Ruger 270 floating barrel question?
If your Ruger is like mine, that isn't actually a burr at the end of the barrel channel it's a pressure pad. The theory is that a light barreled rifle will actually shoot better with a little bit of upward pressure on the barrel. In some cases I've seen it work really well, and in other cases removing the pressure pad and letting the barrel free float allows for better accuracy.
When my Ruger quit shooting as well as it had I tried to figure out what I had changed and finally found that I hadn't torqued the action screws the same as when I was getting better accuracy. I retorqued the screws and my accuracy came back.
The only problem I really have with the pressure pad is that my POI seems to shift a lot depending on the weather due to the stock expanding or contracting. Maybe someone on here with more experience with Rugers could tell you what will work best, but if I were you I'd make sure all my action screws were good and tight and torqued as described in the Ruger manual and see if that fixes your problem.