I have experienced the same problem with my 629 performance center. cylinder intermittently locks up tight......I've sent mine back to s&w for repairs.....
You would think for a $1000.00 plus dollars you would get a reliable firearm....
I have 3 different PC guns and all have had different problems that have required warranty work.
I think Quality Control is at a minimum at the S&W plant... my $0.02