I don't understand the desire to shorten the barrel on a 7mm magnum. To me at least, the 7mm Mag. is a rifle one choses for open country, longer range shooting.
In that sort of hunting a longer (26") barrel isn't going to make much difference in how handy the rifle is when hunting. If any rifle NEEDS more barrel length it is the big magnum rounds that burn a lot of powder and give back a lot of velosity. To trim the barrel on a 7mm Mag. to 22" will basically give you 200-250 fps less velosity and that means it is equivalent to the .280 Rem. Why not just shoot the .280 in the first place and burn less powder??
If your hunting is in thicker terrain where a 4" shorter barrel really is desirable.....shots will likely be shorter and the 7mm Magnum is hardly the first chambering I'd choose. There's no need for the high velosity/flat trajectory that it offers. A .280 or even better .30-06 would be a much better choice at ranges under 250 yards.
...................TR!............Losing 200-250 fps from only a 4" barrel cutdown on a 7mm Mag? Man! You are just a little pesimistic there. LOL! IME, more like 20 to 30 fps per inch or 80 to 120 fps overall. Using the same loads over a chrony, my 300 WSM Ruger carbine with only a 16.5" barrel, retains on average 95.5% to 95.7% of the 24" barreled 300 WSM velocities. The comparison breakdown differences "per inch" were from 16.4 fps to 19.5 fps. Going from a 26" barrel down to 22" on a 7mm Mag, a 50 to a 62.5 fps velocity loss, is too much imo.
Maybe Hillybilly will also take that rifle into some deep timbers? Maybe into some thicker brush? Or maybe up and down and into some space constricting stands? So a 4" barrel cutdown will help in the handier and better manuverability depts. And just maybe while on the same hunt, he might need to perform a 400-500 shot in an open clearing?
If one can handle a little more muzzle blast and some noise (not all THAT much different between a 26" and a 22"), shorter barreled and handier rifle thinking, should not just be restricted to the lesser powerful non-magnum rounds.
By using powerful rounds in more compact rifles, one has the ease in using a handier and easier carrying rifle for the thicker stuff, and then jump immediately if needed to, into some serious long range hunting using the same rifle.
Havin some cake and eatin it too.
