I got this jig to help solder. I will be using it for 5.5mm bullet connectors.
Wow ! Nice acquisition!!! HK Is selling a clone for cheaper! You can use this tool for all bullet connectors (2.3, 3.5, 4, 6mm) as well as Deans/XT60. Use it in conjunction with 3rd hand tool (to hold wire) and you can get that perfect joint!! Enjoy!!