Originally Posted by
typerated
I think this is the wrong way round:
Rather than the USAAF to cannon, the RAF should have gone for 0.50 cal.
We all know the 0.303 is too light and 20mm too slow and low rate of fire for A2A.
Carrying both didn't make up for the deficiencies of the other!
The thinking at the time was one of accuracy. The powers that be weren't that confident of a pilots ability to hit a target and a spread of .303s offered the best chance of hitting a target.
Cannon were thought about pre WW2, but ditched for .303. The 8 gun fighter was a potent weapon when thought of in the mid 30s. The idea was even toyed with 10 or 12 guns. I believe tests were carried out pre war on .5s, but the results were disappointing.