I have been using lead and then lead free .22 pellets to take down squirrels and it always took a head shot. A body shot was never effective and only resulted in the squirrel running off to die in its den. With my new .25 Air Arms Ultimate Shooter I took a chance on a squirrel where only a torso shot was available. The Predator GTO 16.54 gr steel pellet took the squirrel down with one shot to the torso. Within an hour a red shouldered hawk was busy devouring the squirrel (which is why I only use lead-free pellets for hunting).
The 16.54 gr steel pellet provided a much greater kill impact than the JSB Jumbo Exact heavy 18.1 gr lead pellets. The only downside is that I needed to add a 1/4" steel backing plate and a ballistic rubber front to my target backstop with the steel pellets. Much greater penetration with the steel pellets as compared to the lead ones.
The 16.54 gr steel pellet provided a much greater kill impact than the JSB Jumbo Exact heavy 18.1 gr lead pellets. The only downside is that I needed to add a 1/4" steel backing plate and a ballistic rubber front to my target backstop with the steel pellets. Much greater penetration with the steel pellets as compared to the lead ones.