The 3 dram load would kill elk or moose, close up, like perhaps 100yards, but it is a weak load barely making 1,000fps. & also has a fairly high trajectory as well.

My Kodiak .58 regulated with 110gr. 2F and patched balls.
I am glad they did not use slugs in the article, which would have likely diverged by at least a foot at 50yards.

Soft slugs in a SxS is not a good idea due to slug movement off the powder in the non-fired tube, or if/when walking with the muzzle's down.