Good time for a reminder on a common problem with .303 doubles. Most (all?) have fast-twist barrels and were regulated for the 215 gr bullet; sounds like yours still is, Mickey.

BUT.... many were re-regulated for the Mk VII cartridge with its 174gr Spitzer bullet, despite the faster twist, and will no longer successfully shoot the marvellous 215-grainers which are once again plentiful. In Oz, both Woodleigh and Taipan make the 215-gr RN projectile: a bonded-core Premium for game, and a cheapie for the dirt bank. Perfect!

Before tossing down a wad on the Cabelas gun, or any .303 double, I would want to know which bullet weight it was regulated (or re-regulated!) for.