Purchase of certain firearms; age requirement; penalty. Prohibits any person under 21 years of age from purchasing a handgun or assault firearm, with exceptions for the purchase of an assault firearm by a law-enforcement officer, correctional officer, jail officer, or member of the Armed Forces of the United States, the Virginia National Guard, or the National Guard of any other state. Accordingly, the bill prohibits a licensed dealer from selling, renting, trading, or transferring from his inventory a handgun or assault firearm to any person under 21 years of age. A violation of either prohibition is a Class 6 felony. The bill also expands the definition of "assault firearm" as the term applies to criminal history record information checks. This bill is identical to HB 1174.