They probably will be back sooner or later.
I used to give dogs at least one free pass, but not any more.
A few years back there were two dogs running around the area that belonged to someone several miles away. I saw them at least three times and let them go every time, once even giving them a couple warning shots from a .22 mag. Then one day I caught them chasing deer in our back pasture, as Sam said, they got .270'd.
No more problems.
