I've scoured the internet, and sent emails to various airsoft shops and this is my last effort to hope someone has info on this issue.
I have a King Arms medium size M203 40mm under barrel grenade launcher, and the barrel latch, the thumb lever that you push to disengage the lock to slide the barrel open has snapped, it appears to be cheap pot metal.
I am now on the hunt for a replacement part as this obviously renders this launcher useless.
Any help locating a part would be greatly appreciated.
I did find a post of my exact issue in a UK forum, but it appears there was no solution.