In the realm of practicality, whether a swamped or straight bbl is more accurate, is quite academic. Fairly accurate, useable loads can be developed in both types of bbls, but these loads wouldn't be considered accurate by target shooters and definiely not by the bench guys. These 2 classes of shooters use straight bbls of greater dias to suit their needs...target shooting demands a muzzle heavy rifle and bench shooters demand a large dia, straight OD for consistency. The reason swamped bbls came into existence is unknown...we can surmise why it happened...easier to make by forging, lighter bbl w/ a heavy breech to withstand greater pressures, better balance, lower front sight vs a taller one w/ a straight tapered bbl, aethetics and some other guesses not mentioned. Asre harmonics and bbl deflection yrs back...don't think there's evidence that it was even considered, but then again, we definitely don't know the reasons for a lot of things.....Fred