If memory serves, and it always doesn;t. the USAS was banned at the same time as the Street Sweeper, because it had a “spreader’” muzzle being larger than the bore. This in my recall and it has been a long time. I never saw a round magazine, but the box magazine was 10 round, again as I recall.
barbra ann
It certainly is an awesome weapon with a rather limited range of utility.
Sure would be fun to have one if I owned a shotshell ammo plant!