Polymags: Squirrel vs Backstop

Hi

i haven’t used polymags and have a Wildcat .25 MK2, I had a question about using polymags, I understand they expand on impact day hitting a squirrel or whatever, so they are good for that purpose, but when they hit say my backstop, would they be more destructive like when they hit a squirrel or less destructive than the lead .25 pellet as hitting a surface it’s not purpose made for?



open to your thoughts