Same here. It's not the caliber, it's just a crappy round,. Usually underpowered and a tumbler, coming out of a crap gun. The only reason it exists is because it's just big enough to be a center fire, which is what Browning? ( I think) wanted.Personally, I would not depend on a .25 as a defense round. I know of a SO deputy that got shot with .25 up close and personal. Now understand he was shot by a dirtbag who most likely was shooting said gun for the first time. Unlike the OPs friend this dirtbag did not kill the LEO, the dirtbag did hit the officer in the head but all the round did was take a lap and a half under skin plowing a furrow ending dead center of the LEO's forehead. The shot did though take the LEO out of the fight, which I guess is the idea in a self -defense shooting, stopping the threat, or in this case the arrest. Though only for a bit, the dirtbag was later caught and arrested.
NOTE: I have been speaking of pistol rounds. I have no idea how it would work in a rifle. No experience with it.