Bullet Connectors - flux or not to flux?

[Bondonutz]

MUST FLUX EVERYTHING !

When doing the EC5's I tin the wire and I'll puddle up some solder in the bullet and while still molten insert the wire. if the solder cools to quickly prior to getting the wire in just put irons tip on outside of the connector till molten again. If theres some dribble on the outside it'll still slide into the plastic plug with no problem, I use a small screw driver to push them in cause they're still pretty warm. Have yet to have a failure with any of the over 40 plugs I'll soldered.