Well I've got light strikes as well with my Spartan (7.62X39) and due to US trade restrictions there is no available 7.62X39 brass in Canada right now.
When I cock the gun the cocking lever is very close to the grip of the stock and my knuckles barely clear....then when the trigger is pulled the hammer drops and hits the cocking lever driving it further away from the stock where I feel it should have been in the first place!
Obviously while the hammer is impacting the cocking mechanism it is also being slowed down to the point where it does not even scratch a military primer.
It seems to me like the engagement of the lock up latch is not correct and needs to be re fitted to allow the cocking lever to travel further down so as not to interfere with the hammer.
Has anyone else noticed the movement of the cocking lever when firing?
Here are some pictures and measurements of my rifle.
Knuckle clearance
Before firing
After firing
Barrel removed to show max lever travel