Not at all true.I fired my a-bolt with boss once at a deer and the deer dropped but my ears range for an hour or so.Subsequent hearing tests showed not noticeable loss in hearing.A club member was not so lucky,as a single shot out of his braked 300win magcaused his ears to ring for several hours and he suffered noticeable hearing loss after that one shot.He did kill the elk but he paid a heavy price.