Dave:
You will be interested in this anecdote, from memory it was Aagard hunting with a friend in Africa. Said friend had a Mannlicher Schoenauer with double set triggers and a pop-up cheek-piece for the detachable scope. Aagard was close behind his friend as he stalked a large lion. Being close and ready to fire, the friend set the hair-trigger, then shouldered the rifle at which point he discovered that the cheek-piece was still down and he couldn't get a good sight-picture through the scope. He then pressed the button to pop up the cheek-piece, whereupon the rifle instantly discharged! The slight jarring of the cheek-piece as it popped into position was enough to release the sear. Luckily, the shot went harmlessly into the dirt, and even more luckily the startled lion decided to depart rather than fight!

Perhaps there's a lesson here for you too?

Marvellous rifle, by the way. I love the little 1903 carbine, they are such a delight to carry and shoot.