I found some 4bore plastic cases, 4 inches long, red
colored, looking like an oversize 12ga Activ case, They are all
plastic without a steel insert in the base like Activ cases
have. No markings. I understand they are Fiocchi.
They are the size for the 4bores that are about
.950 inch bore. They are suitable for shot loads of moderate
pressures. Guys loading them say they stretch out after
a few loads. And they use about 3 oz shot.
I will test them with a light buckshot loads
of nine 45cal buckshot, 140 grains each.
Total 1260gr, a little less than three ounces.
In picture are plastic cases with brass ones and 3.3" 8ga.
The base of case will be shimmed with strong wide tape to
fit our chamber, cutting down on the stretching.Ed