The last .22lr I had misfire was decades ago as a boy scout. I've went through boxes of bulk pack in my rugers and not even that has misfired. I've had all sorts of other strange problems (never get a teflon lube on the rails of a mark III mag and then load 22lr cb's... they can really fly out of that thing), but no problem with misfires. I supposed that rimfire ammo has gotten better, or maybe I have gotten lucky.
If the gun is not damaged from dry firing / weak spring / etc, I would consider that lot of ammo to be suspect and try other stuff. Even a good ammo manufacturer could have a problem and rimfires are more prone to having primer problems than centerfires by their very design. Modern rimfire ammo and firearms should not normally have 2 bad rounds out of 30.