On some calibre rifles chambered for the long BPExpress ctgs., seemingly overweight guns sometimes indicates they may have faster twists designed for heavier bullets.
; One must masrue the twist rates to estabilish what bullet weights they were designed for. Rodd Seyfried ran into this himself and upon checking twist rates, found fast twsits for long heavy bullets, hense more weight in the gun to counter heavier recoil.
: Note that nothing is cast in stone - one MUST measure the rate of twist - some guns are merely overweight.