I've pretty much decided on a 1:9" barrel for my 22/250AI to let me shoot 50 - 70 grain bullets. From various loading data, I've determined that it's not improbable to get 3900 fps out of the 50 grn pills and 3300 fps out of 70 grainers.
My question is, loaded to similiar pressures, is there any appreciable difference in throat erosion with the faster or heavier bullets? I know that barrel erosion is basically the amount of heat applied and the time of exposure, but does hot gas velocity matter at all?

I know a guy that has poured more than 5,000 full steam rounds from his .220 Swift and it's still shooting half inch groups. (Rem 40-X)

I think it's like this....how hot was the barrel just before you fired it? Or in other words, do you take a five shot group and wait for the gun to cool down before shooting it again?

I've not done this, but I bet I can shoot out a barrel in a single afternoon in a good prairie dog town......and with mild loads as well.....

As long as you don't shoot the barrel when it's hot, you'll have no special problems.....Hot means you can't hold the gun by grabbing the barrel in a single hand and lifting it up from rest. If it's too hot to hold on to, quit shooting it.

If the barrel is more than luke warm to your touch let it cool. Powder consumed per round along with good care, determines the bore life of any rifle. The 22-250 has always been noted as being hard on bores. If you take care to keep the barrel cool at all times it will last many more rounds.

I only shot my .22-250 at targets and let the bbl. cool between shots but, nonetheless, my groups doubled after 1300 rounds and I lost 3mm of rifling. The rifle is presently out for the bbl. to be set back and rechambered. All things considered, this is my first and last .22-250