The old 40

[carly_kai]

40 mm that is ...

These hand powered, crew served canons were used for air field defence and later as close in weapons on Canadian warships operating in the Persian Gulf. In a somewhat embarrassing episode, the navy was forced to scour various military museums across Canada to re-equip their fleet during the Gulf War, as replacements had never been purchased.

The gun fired 900 g high explosive 40 × 311R (rimmed) shell at 850 m/s (2,800 ft/s). The rate of fire was normally about 120 rounds per minute, which improved slightly when the barrels were closer to the horizontal as gravity assisted the feeding from the top-mounted magazine.

 

In practice firing rates were closer to 80–100 rpm as the rounds were fed into the breech from four round clips which had to be replaced by hand. The maximum attainable ceiling was 7,200 m (23,600 ft ), but the practical maximum was about 3,800 m (12,500 ft).

 

The L/60 Bofors continue to be the main armament of the Kingston class coastal defence vessel, although the navy is in the midst of a search for a suitable replacement.