Those high round count stages will kill a barrel for sure as will sustained high rates of fire throughout the day as you well know. There's a reason I limit my stages to reasonable round counts.Update for reference on this thread.... 1800 rounds in on my Dasher barrel and I am seeing velocity dropoff of about 30-35fps, still decent accuracy but not as good as when new. Looks like my plan to try lighter weight charges to stretch out barrel life didn't amount to much. About 1300 of the rounds were reduced loads or fireforming, the other 500 were match loads at full velocity. That being said I wasn't exactly kind to the barrel. Typical range trip was 50-75 rounds in about an hour. Never got the barrel smoking hot, but did have a recent match where we had to burn through 20+ rounds in 90 seconds trying to hit a plate behind a spinner. I swear that gunsmiths must have made up that stage just to get more barrel orders.
Got another PVA Dasher barrel on the way. Plus a trainer 223 trainer barrel lol.