Tail gunning is running a lure 20 to 40 ft back, sometimes further, behind your normal set.
In this case, I'm running my probe rigger 50 ft down, in 65 degree water. The rigger above
This is 35 to 40 ft down, back about 40 ft. The theory is that after your primary set goes
By the fish, the lure set back further gives you another shot at them. This can help this
Time of year, when the fish tend to follow your set. Another reason is when the fish are
High in the water column, they can be spooky and this gets the lures away from the boat.
I've been running j plugs, Lyman's and mag spoons this way.