Jim,

My post scrolled off the server, but I think at the bottom of that post
I mentioned speedloaders for your rig would be a challenge.

Gunner's suggestion would likely work as long as the cartridges will all
fall through smoothly. Any attempt to push a stack into the tube is
going to result in the first round being pushed against the side of the
tube by the next round, preventing it from sliding down the tube. Might
just take gravity and a little gentle shaking to make it work.

My suggestion is to convince your daughter that tube magazines are
vastly superior, and as a caring father, you'd be willing to swap your
beloved rifle for hers. G

Jon