Same as if it was not approved, they refund it. Those with approved Form 1s but haven't built yet can likewise send a letter to ATF saying it was never built and request a refund. Those who already have theirs are screwed.
But I doubt it will pass, suppressors have become mainstream in the last dozen years or so. Every time I go to an outdoor public range I see at least 1 rifle with a suppressor being shot.
I got Quizzed on this yesterday by a friend...had not heard about it till now.
I thought the Hearing protection act was going to fix this forever.
NOT A POLITICAL POST!
I read an article today online recommending first hunting rifles for kids, one piece of advice was suppressing it.
my kids dont shoot unsuppressed as much as possible. bird hunting is the only notable exception.
to the point they whine, why cant they take a suppressor for riflery at camp!
reason being, I dont want their hearing shot like mine.