?????

I just looked at mine to see what could cause the problem. It's a one piece guard with quite tight fitting pieces. The release lever inside the front of the trigger guard has a heavy spring in it. If this does not describe yours it may point out the problem.

What do you see on yours that might be the problem?

The spring in mine is so heavy that it's difficult to push on the button in the trigger guard. Take the guard off and see if you can see a torsion spring. If you can maybe Kimber will mail you a new one? There is a drive pin evident thru the guard which must take it apart.

By the way when the floor plate opens does it hit the stock near the hinge? If it does then there is a change in the shape of the floor plate that will eliminate that.

They will require that the entire rifle be returned for that change.