Yes because it is copper.
For a bullet to be legal in a ML here in Idaho it must be made of lead. It also must be within .010" of bore diameter. Sabots are illegal, pellets are illegal, 209 primers and centerfire primers are illegal. Scopes are only allowed IF the person has a doctor give them permission because of eyesight problems. The cap must also be exposed to the weather.

Most of the rifles that are on this forum are illegal in idaho. OUr rules are brought up by both F&G people and the public. Inlines were illegal a few years ago. Some stink was raised and the rule was dropped but an inline must still have an exposed cap.

Ron