If you want a carbine, consider looking for a used Steyr SBS Mountain in .260 Remington or 7mm-08.
I have an 18-inch Parkerized Mauser .308, a 20-inch Steyr M in .270, a BRNO 21-inch full stocked 7x64. They all give up too much velocity, not for trajectory, but for delivery of energy at 300 yards. Only the .270 Winchester still has the stuff. Surprisingly, the same was true for a .270 Ruger RSI.
You are right about not wanting a thin barrel, too. If you are winded, you want more weight out there when trying to aim, especially if you have no rest for the rifle.
The shorter barrels are much handier in the hands and on the back. 24-inches is too long to carry the rifle muzzle down in one hand on steep ground without risk of stuffing the muzzle into the Earth. My Mauser wears an HK G3 flashider to protect the muzzle, with the military G3 plastic cap to keep out rain and dirt. It has no scope at all, just a rugged aperture sight with 3 settings of 100, 200, and 300 meters - one click to each one. Shoots sub-MOA 5 shot groups, but only gets 2,600 fps from 150-gr ammo.
There was a guy trying to sell a Steyr 7mm-08 over the holidays for $450, no takers. Probably a great rifle but....
http://www.thehighroad.org/showthread.php?t=475368&highlight=STEYR+7MM-08Muzzle down not touching the ground is a must for me.
Howa 1500 is a great action, but heavy due to relatively beefy build and metal alloy trigger\floor plate assy. Picked up their SS, laminated stock offering in .270 at the store, then put it down, pretty damn heavy. Found a used 700 LSS Mt. rifle, kinda ugly, but practical.
