...heard the same reports regarding hevi-shot...tho also heard that hevi-shot may not be the best shot for highly prized double guns (read, high ticket english or continental doubles)...seems to work perfectly well with field-grade doubles/autos/pumps...

...gazalans.com/conneticut shotgun has some info on bismuth/hevi-shot for reference purposes...you may also wish to check federal ammunition's website...