Harry,Tim here. Follow up shots? These guys are in the lake,& only show there heads above water,If they are spooked,they dive down in an instant! I would not think anything other than a direct head shot would be appropriate.(Im shure the 350 would have no problem going thru the shell) It was very obvious when I had a "confirmed kill",, the water is clear& you could see the "perp." sinking to the bottom, as opposed to swimming off. Man that was great fun! Today I painstaikenly mounted "glass" on my new 350 Its doing great!! Cant wait to get back to the pond!! In the meantime,today while I was on the Ph. W Harv., I noticed the "carpenter" bees are boring new holes in my porch rafters,time to get out my XX,s,Great fun!! Man I forgot about that! The fun never ends for us dedicated airgunners,its year round!! Tim.