I read a couple posts touting the 280 AI and I was wondering how close that would be to the 7mm Remington Mag?

What are your thoughts on AI in general? Is it worth it? What rounds gain the most benefit from such a conversion?

At comparable pressures, in equal length barrels, a 280AI can get within 50-100 FPS of the 7 RMAG, while using a good bit less powder, at least with bullets of 140 - 154 grains, in my experience. Never tried the heavier bullets.

I had a 250 Savage AI, and currently have a 257AI and 280AI. Performance-wise, they do what I need them to do, and, they look really neat with their nearly straight-sided cases and sharp shoulders

R-WEST

I shoot a 7mm RM and a 280ai and other than a little speed the biggest differences I see are case life and powder consumption (recoil). However, I have never tried anything bigger than 150s in the 280. The 280ai was a rebarreled 30-06 Win 70 with no smithing and it feeds and shoots well. It's not super accurate during case forming like my 223ai so next cases will try 30-06 sized to have a false shoulder. Neck sizing is all that's needed and no trimming. You can't go wrong.

The .280 Ackley can get within about 100 fps of the 7mm mag with 140 and 150 grain bullets--sometimes a little more than that. The magnum case really comes into its own with 160 and 175g bullets and the disparity is much greater. This assumes that both cases are loaded to the same pressure levels.