FX Wildcat 1st generation and slugs

Hello , I get a FX Wildcat 1st generation in .25 , with the "old" smooth twist barrel , smooth bore and rifled on the last 10" . Very accurate and much more consistent than the liner system , never POI shifting problem with the JSB 25gr. at 790 Ft/s.
Now I tried some FX Hybrid slugs , but accuracy was not that good. So I wonder if someone tried to shoot slugs in that kind of barrel , what brand , speed or settings used ?
Thanks.
 
My bobcat prefers 25.4gr Kings more than anything else. If you can get your paws on FX Kings give them a try. They outperformed JSB brand kings in my gun. And, as others stated, slugs don't fair all that well from ST barrels. Hybrids will group 2-3" at 100 yards. That's the best I've found, so far. Curious if the new Halo "projectiles" will do well in classic ST barrels. My Royale and Bobcat would be grateful. 😊