OK, I'm going to stick my neck out here but I believe that with normal use, that is not getting the barrel red-hot, a Garand barrel should last about 5K rounds before you should consider replacing it. I recall shooting the Commander's Matches with the Garand, which included timed fire, and got the barrel hot but never shot it out.
I can also tell you that under combat those old rifles would get too hot to handle but they never shut down or seemed to lose their accuracy but we weren't dealing with national match rifles then, except for a few snipers, so losing a moa didn't matter muc at long as they hit all the way out to the berms. Mikey.