something is wrong if you shot it out with 1300 rounds. It took about 4000 for a .220 Swift and most of these were at 4000 fps.

You kinda answered your own question..if pressures are kept equal there will be no difference. I agree with JStevens, Andre. Your experience is very unusual. 22-250AIs should last more or less as long as 223s, all else equal.

I shot a Ruger #1 Varminter at prairie dogs for about ten years. During that time I shot out three barrels, but got close to 4500 rounds from each barrel before it needed replacing. When I did replace a barrel, I sent it back to Ruger where they installed a factory (heavy) barrel.

I think the main thing that shoots out a barrel is heat. Fred Smith at Bullberry told me that every few minutes while shooting, I should grab onto the barrel in front of the forepiece with my bare hand and if it was hotter than I wanted to hang onto, GIVE IT A REST. He said that would be about 120 deg F at the forepiece and would mean the chamber and throat area is getting hotter than it should. Well, of course I violated that rule rather regularly and shot out my barrel after 4500 rounds. And I mean shot out. I could drop a bullet into the throat and it would go in about an inch past the end of the brass. Also the accuracy was dropping off pretty badly.

Don Shearer