There are no stupid questions, only stupid responses!
Depends on what you want to do... and honestly there are so many "what if" scenarios that you shouldn't look at it from a "semi vs. bolt" comparison. Obviously you won't consume as much with a bolt action vs. semi, so as a rule of thumb you could stick with that.
If however you're going to rely on your bolt for "real" work like hunting (barring any discussions around zombie attacks or other silliness) then you may want to stock up more on your bolt action supply... bearing in mind it will cost more since it is typically of higher quality ammo.
So like I said... depends
