4K seems like a big number for it and the round being overbore. Throat erosion will be the biggest factor being a semi, you know you're going to be doing some mag dumps!
Those won't help but they'll sure be fun as hell to do!
I would keep an eye on it, checking it about every 500 rounds and comparing it to when it was new and then say at 250, 500, 750 and then 1K. Also keep track of your accuracy, see how much it changes over time and if it gets really bad, see about having the chamber set back rather than rebarreling it.
I'm thinking at about 2,500 rounds is where you're going to need to do some thinking about what you want to do, cut the chamber or rebarrel it. Maybe @50cal can give us a little bit better info about it and what he saw from when he worked there.