Last summer I had a problem with those big 2 inch long wasps that drag cicada into their nests in our retaining wall, lots of them. I loaded up some 357 Mag cases with 1 grain of bullseye, card wad, steel cut oats and a thin card wad on top. Using my 10" contender barrel at about 10-15 feet I didn't get many, the pattern was way to open as I could see impact marks on the wall. Regular wasp spray was ineffective on them, had to use farm grade malathion sprayed on the wall to get rid of them. The year before I used the grandsons BB gun with good results until I got a ricochet that hit the soffit of the house so that was the end of that. They will be back again this year. Critter control is a full time job anymore.