[perisher]

Extract from U.S.S. TANG (SS 306), Report of Fourth War Patrol 31 July 1944 to 3 September. 1944.

This was a gun attack on a patrol yacht, 14 August 1944.

"1753 Surfaced to maintain contact and check all guns, then
closed
1832 to seven thousand yards and commenced firing. The
enemy was tenacious and wary, twisting and turning and
closing the range at every opportunity, and though he
replied only with apparent 20 mm. machine guns, he was on
in deflection and not far short with a range of 4500
yards, forcing us to haul out frequently.
It was impossible with his movements and the 4" rate
of fire to stay on for more than one or two hits, and only
eight sure hits were observed. These were beauts,
however, demolishing his deck house aft and exploding in
his side and upper works.
1926 With eighty-eight rounds expended and the enemy still
under control, perhaps from central station, proceeded to
the south for patrol on the following day."

I make that 88 rounds in 54 mins, an average ROF of 1.63 rounds per minute, with 10% accuracy.