Like to know whether they symbolize that that the chamber has been certified to be empty,
or they're intended to keep the bolt [carrier group] from going into battery.
You wouldn't want to bet your life that a weaselly little zip tie
would keep a bolt [carrier group] from going into battery.
But you wouldn't want to bet you life that a muscular bolt [carrier group]
could chop through a weaselly little zip tie and be guaranteed to go into battery.