Correct lubrication is important even in ak47. Your trigger and hammer springs should have a tiny spot of gun grease on each coil section the firing pin dry to start. Lube especially 30w non detergent motor oil will find its way in there just lubing the carrier.
I would go ask what trigger setup they used to build the rifle.
"Gun control: The theory that a woman found dead in an alley, raped and strangled with her panty hose, is somehow morally superior to a woman explaining to police how her attacker got that fatal bullet wound." — L. Neil Smith
The problem with being stupid is you cannot simply decide to stop doing dumb things...
"I crapped my pants to avoid the draft!!" -Ted Nugent