I've been putting a 270 AM through the pains of tinkeritus for several years now. Right around 900 high intensity rounds. Bore scope assessment shows "some" signs but not as much as would be expected.
There's a lot of live still in her. Especially now that I've wised up and treat it with respect.
I most probably should have gone with a 338 as the 375 doesn't get you any more than more thump and braggin' rights.
However with some good 375 - 400 class bullets she'll then step out and make a difference. If only beyond 2500 yds.
Follow Kirby's load development instructions and you'll be surprised. I didn't initially. But she's dialed in at this point.