Not surprising considering you're using a thumb size slug for an itty bitty porker.
LOL, you bet Elk, that was my old 500gr Woodleigh load, the damn brush, leaves, dirt and debris made a hell of a chit cloud on the ground after that slug penetrated the pig, they were already nervous and spooled up coming in very cautiously, the BOOM sent them into full flight. cept for one ; ]
