I got the first sample of zinc round balls from Rotometals to test.
Didi a short range/load test yesterday using my K.I.S.S. Coehorn.
For golf ball mortar games the standard load for 30 yards using a golf ball is 25 grains of GOEX Fg in my gun.
For the test I loaded the gun with powder and fired the zinc ball and then measured the distance the ball traveled including roll out.
Metro: tailwond 7 MPH, 80 degrees F, 20% relative humidity.
I started with a fuse test, fuse only and a zinc golf ball range 12".
25 grains, range 22 feet.
35 grains, range 42 feet.
50 grains, range 133 feet.
75 grains, range 201 feet.
80 grains, range 235 feet.
85 grains, range 273 feet.
90 grains, range 322 feet
95 grains, range 277 feet.
We did a second set of tests with a golf ball, a steel golf ball and a zinc golf ball using 95 grains and we observed where the balls landed and and how much roll out they had. . The test weren't real subjective. The observations we made are relevant.
The Golf ball and Zinc balls always landed in about the same area and had considerable roll out. The Zinc ball always had more roll out than the standard Golf ball. The steel ball always hit short and had very lttel roll out.
Ball weights.
Golf ball 710 grains
Zinc ball 4313 grains
Steel ball 4938 grains
20 shots would not make the statistician but it gives some ideas where to go.