As tahoe1305 just noted, a SAAMI chambered 7mm WSM can have an OAL over 3". Working backwards from his and Berger's numbers of a "nose length" of .874", the rifling on his SAAMI started about .096" from the front of a 2.1" case. Some modern high-BC bullets add length to the ogive rather than to the full diameter shank, so they don't necessarily need a long freebore.
In a recent thread, a gunsmith added freebore length when it was not needed because he incorrectly thought that the "long, high BC" bullets needed it. As it turned out, the shooter was using a Berger bullet and most of the added length was in the ogive. Some of his shorter bullets would fall out of the case before encountering the