igbal,

...i should not think so, given that most beretta barrels are chrome-lined, and chrome is supposed to be harder than steel...tho i do recall back in 1998-99 when the 470 silver hawk s-by-s was first released that a warning was given about the use of sheet shot in the fixed choke barrels...

...just to be sure, why don't you call beretta usa (given that many sheet shot users reside stateside) and ask?...you may wish to try jhonny, the customer service rep, at 1.800.636.3420...

...best of luck...