In 1972, I knew several guys who made their own blow guns. They would roll up thick material into a cone, then they would put them in the tubes and cut them off flush. Then they'd s stick a nail through the center and secure it. They could hit targets out to amazing distances. These guys were Mormon missionaries and didn't have a lot of money, so on their days off they'd go hunting. They would bag enough squirrels and rabbits to let them eat all week. This spread to other missionaries and it became very popular. (They weren't allowed to use guns, and this was a way they could kill small game and save money.)
Just something you might want to experiment with.
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