Step 1: What you will need
heres what you need for a rifle ( all of this is 1\2 inch schedule 40 unless i say otherwise of course)
1 45 degree
about a 1 1\2' schedule 40 and the hopper is schedule 20 (more space in the pipe so the marshmallow can slid down) doesn't matter how long.
somthing to make holes in schedule 20 pvc pipe (like a power drill) hole cant be too big (see the pic)
wire to match the hole you made in the pipe (see the pic as well (that black thing sticking out of the hole)) you will need a whole ton of it believe me it gets used up quick (about 3 feet)
and of course mini marsh mellows.