You truly will get more with a 22" bbled 7mm Rem Mag: blast and kick.
You will also get less: velocity
Don't do it. I'd cut no less than 24", or as others have said, get a .280 or .280 AI or 30-06 or .270.
I am beginning to wonder if anybody is even reading anything I have posted.
I either already have or have ready access to a .280 AI, .270, .30/06, .308,.300 Wby, .300 H&H, .340 Wby, .350 RM as well as everything from a .17 Remington to .257 Wby.
Read fine, think fine, dumb idea. Knock yourself out, my bet is you've not shot one like it. Maybe think about boring it out to 7STW and cut 'er back to 19"...then you'd have a lot more of what you're after, don't need a new barrel, a reamer and hacksaw are all that's required.
This 7 Mag is a project designed to fit a special niche (Moderate weight, synthetic stocked rifle)at as low a cost as possible.
I am not concerned with pure ballistic performance and I am not looking for a long barreled 9lb plus rifle.
