I posted in your other thread about the same thing. You can shoot a rifled slug in rifle barrel, many do it. It just makes a big mess and is a pain to clean. It won't hurt the barrel though. And some rifled guns shoot a rifled slug very accurately as well.

The modern sabot rounds perform better on game though since they have a controlled expansion design, but they are pretty pricey. I know plenty of people that just won't pay that kind of money and shoot winchester or remington rifled slugs. They don't have any trouble killing deer with them.

As far as recoil, if it is the same weight projectile at the same speed the recoil will be the same.

Paul