Forget OCL, it is meaningless as long as the rounds fit in your magazine. It is the cartridge length measured to the ogive that matters.

If I read what you wrote right, you're figuring that the factory ammo has to jump around half an inch (2.860-7 minus 2.272-2.210)??? Something doesn't seem right, I've never heard of a chamber that long.

If this is correct you are right, most bullets will probably not be seated deep enough in the case and certainly won't fit your magazine if you try to reach the lands.

Alternatively, either I'm misunderstanding your numbers or your chamber measurement is off. The split case method is usually reasonably accurate. The other method that I prefer is a unmodified dummy cartridge with the bullet colors in black Sharpie. Seat progressively deeper until the bolt will close on it, then carefully creep it back re-covering the rifling marks on the ogive each time until the bullet is no longer marked by rifling when you chamber it.