I use EC5 conectors from Hobbycity
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=9194&Product_Name=EC5_5m m_Connector_(Pair)

While the bullet is hot from soldering i slide them into the outer plastic plug untill they rest up against the clip.
Then use a small flat screw driver down the side of the wire to push the bullet past the clip.

Works easy.