That is a good point and I should have been clearer. Alcor, my take was that you were concerned with a minimum or proper amount of Freebore, so my response did only deal with the max. length at which to begin and of course you can tweak a load's length in the pursuit of accuracy. Some reloaders that have older rifles or ones with longer throats, crowd the lands of the barrel a little tighter and use .005" of Freebore. So, I gave an oppinion as a general guideline universally accepted in most reloading manuals. Of course, I could have said, it's in your manual, but I usually have more to say, obviously.
This does refer to OAL maximum and anything shorter is up to you so long as you don't seat too deeply. Pressure increases with a reduction of OACL. The individual rifle has an unique chamber. Pistols do as well and I load pistol ammo similarly, according to the chambers demands. I figured you already had a pretty good handle on that when you mentioned you had the Stoney Point gauge. I will not advise you to crowd the lands, so I think .010" of Freebore is a good place to start when you do change bullets. I believe you understand that I was in fact talking about the Max. OAL to start with, because the manuals recommend OALs similar to factory ammo knowing that the load may end up in many different brands of rifles, and chambers from one rifle to another by the same manufacturer can of course be different based on the machining tolerances an individual manufacturer allows during production.
