Please don't send that sand into your sprinkler heads..... Signed, your sprinkler system.
If you are using the well exclusively for irrigation, why bother with the tank and pressure switch at all? My thoughts would be to use a pump start relay to power on the pump. This way your sprinkler control clock turns the pump on and off. I normally set a sand separator after the pump and before the tank (if there is one).
If you have sand in your system, You need to set any check valve as vertical as possible. (I know, I know, the least number of fittings between the point and pump) There is a reason that check valves are not allowed for backflow prevention, and it is for the very instance that you are experiencing. The sand and sediment basically jams the action, and freezes the spring. Buying a quality part (read: not from a big box store, from a supply house) may help, but the sand will still be there.