Picked up this BF MK14 EBB cheap, came with no mag, a 7.4v battery with no charger (despite them sold with an 11.1v), no flash hider, no bipod
And a couple of issues, receiver mag terminals bent to buggery, mag catch appeared broken, mag prime wasn’t feeding gels to the t piece from the mag
With a little help from @RokSolid @Friendly_Fire and Low Guido’s review video, I decided to pop my teardown cherry and pull it apart to trouble shoot
Bit of exposed wire from the battery to the motor, nothing a little electrical tape won’t fix
Long story short, turned out the mag catch wasn’t broken, just not seated correctly, rectified that issue easily
Receiver terminal leafs were back to front, very tight fit to swap them back around the correct way but got it done with a little effort, not much but did have to take care
Was not ready to pull the gearbox apart
baby steps again lol, but that will be my next venture
Tested the mag prime and mag catch while it was apart, quick test fire
Gels flying out the barrel across my room, success 

Reassembled, gave it another test fire, working like it should. Happy days 
Only issue is I missed reseating the safety switch properly so no safety but I’ll get that sorted easily enough.
Much thanks to the boys for their help and guidance, cheers rok and friendly 