Ackman: I agree on the 221 Remington Fireball cartridge "relishing" the 40 grain bullets from a Rifle length barrel.
Both of my factory stock 221 Remington Fireball Rifles prefer 40 grain bullets (accuracy wise) - one prefers the 40 grain Berger hollow-point and the other prefers the 40 grain Nosler Ballistic Tips.
Rock on - 221 Fireball!
Hold into the wind
VarmintGuy