the 3 groove is supposed to last longer but I haven't seen any hard evidence to prove it ,if you call Dan Lilja he would likely give to the strait and narrow on both of his barrels. The 3 groove is a bit harder on thin skinned bullet like the Bergers and has cause troube with the hot maks blowing the bullets up due to bad jacked deformation , but in the 25-06Ai I doubt that your would push them that hard
What James Jones said.....
As far a barrel life goes. I have a bout 700 rounds through my 270 AM and just gave it a colonoscopy Saturday and the smith said that wear/errosion was not a problem. I didn't tell him how many rounds and he guessed about 400 based on his experience with 300/7mm/30-378 1K shooter's barrels.
Maybe there is a little to the three groove thing??????
But it does tear up 195 gr WCs with I think J3 jackets.
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