The first throw is usually off.
Use a straw from Mcdonalds and insert it into the dispenser tube. Cut it to the length of the closed portion of the dispensing tube. There are some guys making an aluminum reducer for the dispenser tube that is a hot item.
More better explanation of mods.
http://www.primalrights.com/forum/viewtopic.php?t=4585
...and another take.
https://www.youtube.com/watch?v=p-DRJCL0D3A