BF110 shoots himself down?

[Jon]

A question out of interest,
Page 166 of Martin Bowmans book "Mosquito Panic!" describes an encounter between a Mossie and a 110 on the night of 7/8th April 1945.
He describes how the 110 gunner opened fire before the Mosquito had got his guns onto the target, the 110 gunner hit his own tail causing it to catch fire and fall apart and the German aircraft then crashed without the Mosquito firing a shot! ( he got credited with the kill)
How can this have happened, did not all aircraft with gunners have systems set up either electronically or with physical blocks to prevent this type of incident.