Snowball Hit Detection

/summon MinecartCommandBlock ~ ~0.6 ~ {Command:"/kill @e[type=MinecartCommandBlock,r=1]",Riding:{id:MinecartCommandBlock,Command:"/setblock ~-1 ~3 ~-1 chain_command_block 5 replace {Command:\"/kill @e[type=Snowball,tag=copy,score_successCount_min=1]\",auto:1b}",Riding:{id:MinecartCommandBlock,Command:"/setblock ~-1 ~2 ~-1 chain_command_block 1 replace {Command:\"/execute @e[type=Snowball,tag=copy,score_successCount_min=1] ~ ~ ~ /say Hit target\",auto:1b}",Riding:{id:MinecartCommandBlock,Command:"/setblock ~ ~2 ~-1 chain_command_block 4 replace {Command:\"/execute @e[type=Snowball,tag=copy,score_successCount=0] ~ ~ ~ /testfor @e[type=ArmorStand,tag=targetMarker,dy=-1,c=1]\",auto:1b}",Riding:{id:MinecartCommandBlock,Command:"/setblock ~1 ~2 ~-1 chain_command_block 4 replace {Command:\"/execute @e[type=Snowball,tag=copy] ~ ~ ~ /testfor @e[type=ArmorStand,tag=targetMarker,r=0,c=1]\",auto:1b}",Riding:{id:MinecartCommandBlock,Command:"/setblock ~1 ~2 ~ chain_command_block 2 replace {Command:\"/scoreboard players set @e[type=Snowball,tag=copy] successCount 0\",auto:1b}",Riding:{id:MinecartCommandBlock,Command:"/setblock ~ ~2 ~ chain_command_block 5 replace {Command:\"/execute @e[type=ArmorStand,tag=snowballDisp,score_successCount=0] ~ ~80 ~ /kill @e[type=Snowball,tag=copy,c=1,r=0]\",auto:1b}",Riding:{id:MinecartCommandBlock,Command:"/setblock ~-1 ~2 ~ chain_command_block 5 replace {Command:\"/execute @e[type=ArmorStand,tag=snowballDisp,score_successCount=0] ~ ~ ~ /say Hit a block\",auto:1b}",Riding:{id:MinecartCommandBlock,Command:"/setblock ~-1 ~2 ~1 chain_command_block 2 replace {Command:\"/execute @e[type=ArmorStand,tag=snowballDisp] ~ ~ ~ detect ~ ~ ~ air -1 /scoreboard players set @e[type=ArmorStand,c=1,r=0] successCount 1\",auto:1b}",Riding:{id:MinecartCommandBlock,Command:"/setblock ~ ~2 ~1 chain_command_block 4 replace {Command:\"/scoreboard players set @e[type=ArmorStand,tag=snowballDisp] successCount 0\",auto:1b}",Riding:{id:MinecartCommandBlock,Command:"/setblock ~1 ~2 ~1 chain_command_block 4 replace {Command:\"/execute @e[type=ArmorStand,tag=copyDisp] ~ ~ ~ /execute @e[tag=!copyDisp,r=4] ~ ~ ~ /summon ArmorStand ~ ~80 ~ {NoGravity:1,Tags:[\\\"copyDisp\\\",\\\"targetMarker\\\"],Marker:1,Invulnerable:1,Invisible:1}\",auto:1b}",Riding:{id:MinecartCommandBlock,Command:"/setblock ~1 ~1 ~1 chain_command_block 1 replace {Command:\"/execute @e[type=Snowball,tag=copy] ~ ~ ~ /summon Snowball ~ ~-80 ~ {Tags:[\\\"copyDisp\\\"],Riding:{id:ArmorStand,Tags:[\\\"copyDisp\\\",\\\"snowballDisp\\\"],NoGravity:1,Marker:1,Invisible:1,Invulnerable:1}}\",auto:1b}",Riding:{id:MinecartCommandBlock,Command:"/setblock ~ ~1 ~1 chain_command_block 5 replace {Command:\"/scoreboard players tag @e[type=Snowball,tag=!copy,score_successCount_min=1] add copy\",auto:1b}",Riding:{id:MinecartCommandBlock,Command:"/setblock ~-1 ~1 ~1 chain_command_block 5 replace {Command:\"/tp @e[type=Snowball,tag=!copy,score_successCount_min=1] ~ ~80 ~\",auto:1b}",Riding:{id:MinecartCommandBlock,Command:"/setblock ~-1 ~1 ~ chain_command_block 3 replace {Command:\"/execute @e[type=Snowball,tag=!copy] ~ ~ ~ /testfor @e[type=!Player,tag=!tracked,r=5]\",auto:1b}",Riding:{id:MinecartCommandBlock,Command:"/setblock ~ ~1 ~ chain_command_block 4 replace {Command:\"/scoreboard players set @e[type=Snowball,tag=!copy] successCount 0\",auto:1b}",Riding:{id:MinecartCommandBlock,Command:"/setblock ~1 ~1 ~ chain_command_block 4 replace {Command:\"/scoreboard players tag @e[type=Snowball,tag=!tracked] add tracked\",auto:1b}",Riding:{id:MinecartCommandBlock,Command:"/setblock ~1 ~1 ~-1 chain_command_block 3 replace {Command:\"/scoreboard players set @e[type=Snowball,tag=!tracked] successCount 0\",auto:1b}",Riding:{id:MinecartCommandBlock,Command:"/setblock ~ ~1 ~-1 chain_command_block 5 replace {Command:\"/stats entity @e[type=Snowball,tag=!tracked] set SuccessCount @e[type=Snowball,c=1,r=0] successCount\",auto:1b}",Riding:{id:MinecartCommandBlock,Command:"/setblock ~-1 ~1 ~-1 repeating_command_block 5 replace {Command:\"/kill @e[tag=copyDisp]\",auto:1b}",Riding:{id:MinecartCommandBlock,Command:"/scoreboard objectives add successCount dummy",Riding:{id:MinecartCommandBlock,Riding:{id:FallingSand,Block:activator_rail,Time:1,Riding:{id:FallingSand,Block:redstone_block,Time:1}}}}}}}}}}}}}}}}}}}}}}}}