Revolutionary War and War of 1812 Battlefield Protection Act of 2003 - Amends the American Battlefield Protection Act of 1996 to direct the Secretary of the Interior, acting through the American Battlefield Protection Program, to establish an acquisition grant program for battlefields and associated sites identified in the Revolutionary War and War of 1812 Historic Preservation Study (battlefield report).
Authorizes the Secretary to provide grants to States or local governments (eligible entities) to pay the Federal share of the cost of acquiring such sites. Permits eligible entities to acquire an interest in eligible sites using such grants in partnership with nonprofit organizations.
Requires the non-Federal share of the cost of acquisition of eligible sites to be not less than 50 percent of the total.
Subjects acquired property to the Land and Water Conservation Fund Act's prohibition against conversion to other than public outdoor recreation uses without the Secretary's approval.
Requires the Secretary to submit to Congress a report on activities carried out under this Act and updates to the battlefield report.