difficulty in take down

[gman]

I took my VH 16 gauge 0 Frame out on the sporting range today and there were a few times where the safety was off but the gun didn't fire or seemed to have a hard trigger pull - all in the forward trigger for the right barrel. I opened and closed the gun a few times, slide the safety back and forth and finished a few more stations.
When I got home to clean the guns I removed the for-end and slid open the lever
and the action would only partially open and would not separate from the barrels.
I then reassembled the gun, pulled the triggers on some snap caps, and then the gun disassembled fine for me with the gun uncocked and pins visible. I went through the routine again and it still would not come apart unless the forward trigger was pulled. There was no need to pull the left to disassemble the gun.
Definitely at this point a trip to the gunsmith seems in order as I am not one to get deep into it but Im curious if anyone has some insight or has had a similar experience.
Thank you.