My Parker won't cock

[Michael Sutton]

Hello all, I am a gunsmith, but this is the first Parker I have had the pleasure to work on. My original complaint is that it won't cock. I took the bottom plate off, inspected cocking slide, the floor plate, the hammers and the cocking spurs. Without the floor plate attached, I can hold by hand and it cocks like it's supposed to. But as soon as I put the floor plate back on the gun fails to cock. I have racked my brain over this. I rechecked all of the part and none of them seem to have excessive wear. It is a grade 2 Parker in 16 gauge made in 1892 and still has some case hardening color to the protected parts of the shotgun. Everything is tight including the lock up of the barrels on the receiver. I need to ask if anyone has ever come across this problem? Also, if anyone has some suggestion on what to check next I would appreciate it. Most Doubles I have worked on use a different cock type mechanism. I would hate to never be able to shoot this shotgun.

Michael Sutton