I have a Dragonov stock on mine , don't know who made it .
It took some fitting for me to be happy with it , I cut the hump off and shaped the rear so it could be dis assembled like it can with the wood stock , much better .
it got a little loose with age / wear so I used two screws to remove the slop , one at the rear into the stock and one at the front into the stock . Works great .
When you did the swap , could you hear / see the trigger retainer snap in place ?
It may not have been fully in place .
It took some fitting for me to be happy with it , I cut the hump off and shaped the rear so it could be dis assembled like it can with the wood stock , much better .
it got a little loose with age / wear so I used two screws to remove the slop , one at the rear into the stock and one at the front into the stock . Works great .
When you did the swap , could you hear / see the trigger retainer snap in place ?
It may not have been fully in place .