Another consideration before comparing recoil of vintage loads with modern loads would be the weight of powder.

45-49 grains of bulk smokeless vs 22-25 modern powder grains for a 'super pigeon' load would seem to push the recoil, as calculated by a computer recoil calculator, well into the 'ouch' zone.

It's not a great increase in ejecta weight, but that's all transformed into gas at a much higher velocity..... thus the recoil increase as shown by the computer of 25-30%.

If I'm missing something, what is it?