Ok, the battery that I had was indeed a lemon, but it turns out that there is a problem in my gun too. Even with a new battery that the shop supplied (which was tested on site with a gun that is extremely similar), the gun did not fire.
Can anyone tell me what is the most common cause for a click but no firing?
VFC Saber SD Urban Grey - VFC SCAR-L Tan - KWA MP7 Tan
WIP: Magpul FPG Conversion to TM Specs (currently KWA Spec)