In real world terms, if 11 bucks for 50 rounds of ammo is a factor, maybe you should reconsider how bad you really want to kill squirrels. I think the most squirrels i've shot at in a given day is proably 50 or fewer. ITs hard to find an activity that you can have fun doing all day that only costs you 11 bucks.
Another factor to consider is versatility. As a general rule I try to buy a little more gun than needed for my intended purpose. My take is why buy a gun chambered for a round that is good for 50-100 yds when I can get one that is good out to 150-200. I also think the 17 would do better on larger game than the .22 i.e. crows,jack rabbits,bobcats etc. Not that a .22 wont kill them, I just think the 17 would do it more efficiently.
