The preceding data alone are enough to establish the following:
a) There can be no question of the Exodus before a 'Ramesses' had come to the throne in Egypt (11 Kings of Egypt had this name).
b) Moses was born during the reign of the Pharaoh who built the cities of Ramesses and Pithom, i.e. Ramesses II.
c) When Moses was in Midian, the reigning Pharaoh (i.e. Ramesses II) died. The continuation of Moses's story took place during the reign of Ramesses II's successor, Merneptah..............
.....It is known that Ramesses II reigned for 67 years (1301-1235 B.C. according to Drioton and Vandier's chronology, 1290-1224 B.C. according to Rowton). For Merneptah, his successor, the Egyptologists are unable, however, to provide the exact dates of his reign. Nevertheless, it lasted for at least ten years because, as Father de Vaux points out, documents bear witness to the tenth year of his reign. Drioton and Vandier give two possibilities for Merneptah: either a ten-year reign, 1234-1224 B.C., or a twenty-year reign 1224-1204 B.C. Egyptologists have no precise indications whatsoever on how Merneptah's reign came to an end: all that can be said is that after his death, Egypt went through a period of serious internal upheavals lasting nearly 25 years.
Even though the chronological data on these reigns are not very precise, there was no other period during the New Kingdom concordant with the Biblical narration when two successive reigns (apart from Ramesses II-Merneptah) amounted to or surpassed eighty years. The Biblical data concerning Moses's age when he undertook the liberation of his brothers can only come from a time during the successive reigns of Ramesses II and Merneptah [ The period spanning the two reigns Sethos I-Ramesses II, which is said to have lasted roughly eighty years, is out of the question: Sethos I's reign-which was too short for this-does not square with the very long stay in Midian which Moses made as an adult and which took place during the reign of the first of the two Pharaohs he was to know.]. All the evidence points towards the fact that Moses was born at the beginning of Ramesses II's reign, was living in Midian when Ramesses II died after a sixty-seven year reign, and subsequently became the spokesman for the cause of the Hebrews living in Egypt to Merneptah, Ramesses II's son and successor. This episode may have happened in the second half of Merneptah's reign, assuming he reigned twenty years or nearly twenty years. Rowton believes the supposition to be quite feasible. Moses would then have led the Exodus at the end of Merneptah's reign. It could hardly have been otherwise because both the Bible and the Qur'an tell us that Pharaoh perished during the pursuit of the Hebrews leaving the country.
http://www.masmn.org/documents/Books/Maurice_Bucaille/The_Bible_The_Quran_and_Science/069.htm