Section 17. Whoever, in the night time, enters without breaking, or breaks and enters in the day time, a building, ship, vessel, or vehicle, with intent to commit a felony, the owner or any other person lawfully therein being put in fear, shall be punished by imprisonment in the state prison for not more than ten years. Whoever commits any offense described in this section while armed with a firearm, rifle, shotgun, machine gun or assault weapon shall be punished by imprisonment in the state prison for not less than 7 years or in the house of correction for not less than 2 years nor more than 21/2 years.