Rdog,
Stangfish and Jhelmuth have you going in the right direction. As a NRA Mid Range F Class Match Director / RSO, I can assure you that all F Class (Approved / Sanctioned) matches require the rifle to be loaded with one round at a time, regardless of the rifle's capability to hold more ammo. Your mag doesn't have to be dropped nor do you have to modify a mag to only function in single action mode. Keep in mind, T/R stands for Target Rifle, not Tactical Rifle. The area where I correct more competitors is with the lack of use of a ECI (Empty Chamber Indicator). Simply make it part of the rifle and you'll never be wrong.

As for the difference between the actions? I'll run my non-target actions up against the target actions all day long......as will most folks.

Ken