One other thing; the human thumb is not designed to be shaped like a .30-06 cartridge. The M-1 is capable of doing this, regardless of original thumb design.
Most of these children don't know what they missed.............I only got clipped once (OK....twice)....but you'd hear...........wham.....that $%##.......another M1 thumb.
It was a happy day when we were issued the M14s...........