Obviously outvoted here when I said "no". Although I don't own a .25, I can see rhe attraction from a fun point of view and for ratting at sub-12. But wasn't sure if the action would be up to it without having to turn it into a harsh shooting mess. But was only guessing. Go on, have a go and see how it turns out. Variety is the spice of life and all that. Wonder if some extra piston weight might help?
One other lovely thing in addition to the wallop will be the ease of feeding it those big pellets.