I'm also building one and have been pondering the same question.
Asking same question the reamer I'm looking at is a .108" puts a 105 AMax at 2.700" a 87 Vmax @ 2.630" a 108ELDM @ 2.722" and a 105 RDF @ 2.745" wondering if I should run it out to .126 fore a freebore.
Varmint silhouette rifle, Phil?