I have a backstop made from 2 sheets 5x8 3/8" thick stood vertically with 5 feet of clay fill in front of them retained by a railroad tie wall. Between the clay and the steel, nothing gets through.
I would do a .260 or 6.5 Creedmore. You have plenty of bullet options and you could always get a Wyatt's extendable mag box to allow long O.A.L. rounds to feed in your rifle. The .260/6.5 will have less recoil compared to the 7mm-08 and push the high BC 140s around 2700fps in a 24" barrel...
My solution? I am going to build a 7-08. I want a 22-24" tube, 1-9 twist (for heavier bullets) with a heavy contour. Similar to the sendero contour on my swift. From my reading, 7-08 still shines with the shorter barrel. I know I can get 2800 fps with 150ish grain bullets. I like the...