Re: 7mm vs 280ai
A few questions first. Do you plan to shoot a varied assortment of bullets or are you more inclined to shoot heavy (160 or heavier) or lighter bullets? If you are more inclined to shoot 140s and 120s the 280 AI is a no brainer, less powder, recoil, noise, barrel wear, etc....less of everything except velocity.
If you plan to shoot the heavy for caliber 168 and 180g bullets a properly throated 7Mag will beat the 280 AI by a small margin in the velocity dept. Is it worth the slight edge in velocity it has over the 280 AI? IMO no. With this you have more powder, recoil, barrel wear...blah..blah...blah.
I have had multiple 7mags and multiple 280 AI's. I no longer have any 7mags and still have multiple 280 AI's. I am a fan and IMO is one of the best cartridges available for many reasons. Easyto get brass, easy on brass, performance with a wide range of bullet weights, recoil, and one of the most important ACCURACY.
The 280 AI's simply shoot. They are typically not finnicky when reloading for as compared to the 7mag that can be tempermental. I have never had a 280 AI that wouldnt shoot. The 280 AI is just one of those rounds that is inherently accurate!
The 280 AI's I have are throated differently. One is throated for 140g bullets and the other is .188 freebore for 160's and higher, speciffically for the 180 berger. I find I never shoot the lighter bullets in the 280 any longer. With the long throated rifle 26" barrel I get 3000 fps out of the 168 Bergers and 2900 fps out of the 180s. With these loads brass life is good 4-5 loadings before they start showing signs of loosening up. Trajectory wise they are more or less equals, the 180 bucks the wind slightly better but the 180s shoot better past 600 yards in my rifle so that is what I shoot.
One thing of note about the 280 AI that I have seen repeated in every one I have owned is that accuracy is typically found at higher preassures, to a point of course, use common sense. They like to be pushed.
Hope this helps you out. Both cartridges are great but I am a fan of the 280 AI. Good luck im sure either one will serve your purpose great.