Overbore has become a term which gets tossed around but has very little to do with reality these days with our modern powder formulas.
It's a term out of history.
In that same vein so is the concept of a barrel burner. Modern, cooler burning powders with new additives and coatings means that throats erode much less rapidly than before.
You internet theorist nincompoop's really crack me up, in the new Hodgdon,IMR,Winchester basic reloading manual published JAN 2010 under powder descriptions "RETUMBO This magnum powder was designed expressly for the really large OVER-BORED cartridges".
Also one other misconception you have is that these new powders are of a slower burn rate not a cooler burn rate. you must think Retumbo shoot's popsicles out the muzzle
RC
