Certainly in the case of the Purdey Thumbhole type opening guns; which are described as 'Snap' actions or the Number 1 and Number 2 Purdey snap action do close this way. I have a Number 2 snap and it would be very dificult to close by holding the thumb lever whilst closing. Gently bring the action up to the barrels and there is a distinct snap! on closing. As this was the original type of action to the Purdey double underbolts seen most commonly on doubles today I suppose it was meant to work this way. Lagopus.....
