My Butler Creek barrels all came with a note saying cleaning was not necessary unless an obstruction was present. Those barrels have held squirrel accurate for over 8,000 rounds with no cleaning.

As for my centerfire rifles, The only one I ever followed was my FP in 308. That went over 500 before I lost MOA @ 500. I typically don't do a full on scrub until that range. I do snake it around every hundred or so.