Thread: Does a bull barrel help reduce throat erosion?

So how is it that a target rifle barrel that fires 10 to 15 rounds in a short session can have a barrel life of 4000 rounds?
And these are generally high up in the PSI stakes driving 155 grain bullets at the 3000 fps mark.
I get it that they have heavy profile barrels but it cant all be about heat sink or the last few shots in a 15 round string would be way off the mark?