[Rapier]

Good question,
If you are using a firearm of any kind with a magazine and intend on using that magazine to feed multiple rounds, the magazine length must be taken into consideration as well as the bolt face to lands length. However, the rolls reverse and the magazine becomes the absolute control. The nominal magazine OAL setup is the actual internal magazine length less .050 inches. I have at times gotten away with a bit less in a non critical set, but it is reccomended that an OAL be set with .050 clearance and for a critical set (DG hunting, defense, etc), that is what you want to do.

The Pope method of reloading and OAL setting is for single shot application and in the vast majority of shooting intended for and used with cast bullets. The cases are not resized, only deprimed and primed, a powder charge added with or without a buffer or wad, then the bullet set into the case mouth. The bullet is pulled out to extend the OAL past its final set, just before loading, which then allows the lands to set the exact OAL when the chamber is closed. You have absolute zero OAL clearance in the chamber and if the chamber is setup correctly you are centered X centered; with the bullet nose centered in the lands and the bullet base centered and supported by the case neck right up to the transition of the base leaving the neck. The result can be extreame accuracy with cast bullets. This method of reloading while accurate has some drawbacks mainly due to the loose bullet.
Best,
Ed