The British feared that Duilio and Dandolo, which were already well-armored, could fire on Malta's shore batteries, destroying them one after the other, while keeping outside the effective range of the batteries' guns. But the British Army's concerns had no immediate effect on London bureaucracy; until the Italians launched Duilio in May 1876, London made no decision. The Royal Navy finally responded, requesting proposals from British arms manufacturers for a gun capable of piercing 36-inch steel at 1000 yd (900 mm at 900 m).