This is a well known and widespread problem with single trigger IZh 27/MP 27. Although it uses an old and proven British mechanism, designed for sport rifles (without barrel selector), they still managed to screw it up... For every Baikal shotgun, especially for the single trigger MP 27 it is more than advisable to remove the stock and then to clean the mechanism real well - like flushing it with brake cleaner. You would be amazed at the amount of gunk and metal shavings that is left by the factory in there. Most of the time this is enough for the shotgun to start behaving like it should. If this doesn't help than a trip to a gunsmith is needed to inspect, clean and polish the parts - they are quite rough and this is part of the problem. Other well known problem with IZh 27/MP 27 is stocks cracking at the grip - poor mating surface to the receiver is to blame. It is advisable, especially if shooting heavy loads, to bed the stock to the action with epoxy.
P.S. Isn't it amazing how, despite the two independent safeties - inertial block and hammer interceptors, the gun still manages to shoot both barrels at once. Makes one feel real confident with his gun's safety...
