What bullet grain is a mossberg and sons inc model No 45 B?

Your Mossberg model 45B is chambered in .22 S,L,or LR. caliber.As such it will take a bullet weight from 30gr to 45gr which is loaded in today,s ammo.I shoot the 40gr. Lead soft point bullets through my Browning A-bolt rifle with great accuracy.These are the Remington Thunderbolt ammo.Many a squirrel has fallen victim to this rifle and ammo combination thru the years.