New to the forum but looking to pick a few brains about a wildcat idea. My current rifle is a Stevens 200 in 7mm-08. Shoots everything under 150's great but the twist is 1-11 sporter contour and only a 22" barrel. Here is the idea though.

There's a plethora of cheap 7mm Rem Mag takeoff barrels available. 24",magnum contour, 9.5 twist, and the same small shank as mine. So I take a 7 mag barrel, mill the chamber end off to the length of a 7mm-08. That should give me a cartridge that's the same length as my 7-08 with a sharper shoulder that I should be able to neck size with my same collet die. Slight larger case though that is less important to me.

Now for the problems. Brass. Option one is to use 6.5x.284 brass trimmed, then fireformed to the new chamber since it uses the same .473 boltface. Option 2 is maybe switch the bolthead to a WSM and use 7mm WSM brass by milling down a (also highly available) 7mm full length die.
Anyone see major problems with this?

I know there will be the obligatory "just buy a new barrel" and "why not just buy or shoot a .xxx" statements. Part is because I think I can and part is because I think it can be done for cheap. A new barrel is at least $200 -$250. This could put me out $50 if I can do most of it myself while having the added factor of having something unique. It just might be a pretty good little round.