JMR40,
Good point about the .270. I have shot several .270 barrels out, with NO competition shooting, which obviously would decrease barrel life. In fact I shot out the barrel of my very first .270 (a Remington 700 ADL purchased new in 1974) because it shot so well I was FASCINATED by whacking away with various loads. Plus, I still had it after purchasing my first chronograph five years later, so had to shoot it quite a bit more to see what happened with various loads.
Have yet to shoot out a 6.5 Creedmoor barrel, mostly because I keep trying more of them to see if my initial results (with a Ruger 77 Hawkeye purchased in 2010) were aberrations. It's very first 5-shot group at 100 yards, with Hornady 140-grain factory ammo, measured around .6 inch. I somewhat foolishly sold that rifle a year or two later, because of figuring (1) I'd covered handloading the 6.5 Creedmoor for all time, and (2) I didn't know it would become SO popular.
Have now owned six 6.5 Creedmoors, and extensively shot four others, both factory and semi-custom, such as H-S Precision. The WORST any of them shot was 5 shots in an inch at 100 yards, and my present rifle (a Bergara B-14 Ridge) is pretty much a one-holer with factory ammo. Haven't handloaded for it yet.
But when and if I do shoot out a 6.5 Creedmoor barrel, I would expect it to last at least 3500-4000 rounds in normal hunting use, where the barrel is rarely heated up much.
