Belted:

Year this issue was addressed inGuns and Ammo IIRC.

Anyway, the fix was easy. Remove the safety and grind a bevel on the leading edge. Give it a good rubdown with cold blue and the problem was said to be solved.

Why I remember this I cannot say, because I've never owned a No. 1!

Regardless, it sounds right, tho as you say, it seems ludicrous that a gun would be made for so long with such a strange, albeit minor, flaw.