here is a bit more info about different ammo shot from saiga 20:
Brand of ammo,Country_Shell size, mm_Shot size, N (respectively)
Baikal, Russia 20x70 5
Federal, USA 20x76 Mag. 7 1/2
Federal, USA 20x76 Mag. 4
Federal, USA 20x70 4
Bellot Sellier, Czech R. 20x76 Mag. 5
Winchester, USA 20x76 Mag. 6
Winchester, USA 20x76 Mag. 4
Horrido, Germany 20x76 5
Tunet,