The target used was the ISSF target used for air pistols at 10 meters, which should be readily available in most countries. It was not possible to use the copied-down ISSF target with the 20 cm black, as it was raining in squalls like a tropical monsoon, and normal office copy paper would have disintegrated in less than a minute. And the card targets didn't last long either. A friend on the 100 meter firing point, trying to shoot a 15-shot round, had to give up when his target simply collapsed and fell off the frame. As it was, I had to run out to get this target, dab off the water which was running down, and lay it out to dry for some time before even packing it loosely into my shooting box with the other soggy targets.
FWIW, here are the dimension:
10 ring 11,5 mm
9 ring 27,5 mm
8 ring 43,5 mm
7 ring 59,5 mm
10x ring 5 mm
At first glance this seems to be an odd series, but like the standard 50 meter target for the .22s, it is supposed to give a round-number (16mm) progression, apart from the 10x, when evaluated according to the center of the shot hole, the effective "inner edge" scoring sizes then being 7, 23, 39, 54 (when using 0.17" / 4.45mm air rifle/pistol projectiles) and the 10X means that the shot would be touching an 0.5 mm spot!