These are for smooth bore barrels correct ?

Yes, they are (were) basically designed for smooth bores. 90% of the time.

Uncle Matt (in IL)

100% actually. The "Rifling" does not really impart a spin on the projectile. But instead, the "Grooves" are there to allow the chunk-o-lead pass through any constriction at the muzzle. A.K.A the choke. If you have a interchangable choke in your gun, you can install a rifled choke tube, allowing you to fire a saboted slug out of your "smoothbore" NEVER fire a slug out of any choke other than cylinder bore, or rifled choke tube.

I agree with pharaoh2 I learned a hard lesson when I shot a slug through a mod choke tube with my mossberg 500 the barrel had a 8 inch rip in it from then on its the slug barrel for slugs and the bird barrel for shot period