We've had a big weekend on the road, but I was able to get a few minutes on the ranch yesterday morning (in the rain!) to run a couple cartridges through the WR.

6 o'clock hold on the black circle
Fired over 50yd leaf at 50yds
Essentially no distress to cartridge hulls whatsoever, except for very slight moist fouling in case mouth -- no burn at all anywhere.
White plastic base wad totally unaffected.
Massive smoke plume and glorious muzzle report.

Cheddite 2-3/4" paper hulls
140gr Goex FFg
3/8" lubricated hard felt wad
1/8" lubricated donut felt wad
.672" roundball
Ball seats at case mouth
No chrono reading
Fired right, walked 50yds to target, walked back fired left.

Right barrel prints to right
Left barrel prints to left
Vertical dispersion could easily have been from hold

Next time out hopefully I will have more time, I'll try similar ball, 160gr Goex
I will also try Swiss powder in 1-1/2F and 2f
I will also be trying slightly larger diameter ball.

Cheers
Tinker