toss that tip out, melting the thing in is kinda dangerous, even though you probably wont get hurt it would suck to have the thing pop in your hand and then have to start over.
and get something threaded, kinda like this
from left to right:
10-32 threaded mini hose barb, this is what you want for making a mini that is injected with butane, the threads will seal your hole allowing you to just drill it and self thread/tap the hole.
10-32 to 1/4" npt swivel fitting, for increasing the fine threaded 10-32 end to a 1/4" npt for water pipes
check out this site they got some oddball paintball stuff they probably got the same stuff
http://www.palmer-pursuit.com/catalog/fittings.htm
10-32 swivel hose barb, same as the last but its a bigger hose barb (made for vinyl or poly tube 1/8")
10-32 square 90 deg. elbow, this is just an elbow , self explanitory