World at War: 700 Yards Mayhem - British Sniper vs German Sniper - No4 MKI T!

[Alan de Enfield]

.......... but there is a logical explanation that is probably a good story, if only I knew it."

The quality of the Winchester ammunition was very inconsistent, (size varations) resulting in jamming and blockages. It is not so difficult to clear a jam in your Enfield but not so easy when the gun is on the wing of your Spitfire.

Investigations into shot-down aircraft (and the loss of the pilots) showed that their guns were jammed and those had all been using Winchester 'for use in aircraft' ammunition.

Subsequently all Winchester manufactured 303 was banned from use in aircraft, and only allowed to be used for "ground use" and for some early batches only for "ground practice" use.

Now you know the 'story'.