If you want to shoot snakes on your place, shoot them. I have a country house and the thing that will keep the wife, daughters, daughter-in-laws, and grandkids away are snakes. I manage all the animals on my property, they don't manage me. When snakes start paying the taxes, the utilities, feed costs and upkeep, they can stay. Until then they all meet the same fate.
The lady that owned this property before me was bitten by a Timber Rattler while she was working in the flower bed. Luckily we are only about 20 minutes from a hospital. I have killed countless Copperheads in the watered areas around the house. They like the cool wet grass there.
I have used a 2" model 15 and a 3" model 60 with CCI shot loads. Accounted for several large rat snakes in my chicken house. Two quick rounds of it in the barn in the twilight when I couldn't see my sights scored a large opossum that had been bursting open all my feed sacks.
Also loaded some #12 shot in CCI capsules in a .44 Special Charter Bulldog to good effect. The good thing about using shot in your farmyard area is you don't have to worry about ricochets. Also they won't blow holes in the walls of the chicken house.
Please, no stories about how rat snakes eat mice and rats. I have a barn cat that eats all of those she can find. She will eat three a day to the rat snakes one a week.