Film speeds and cameras may indeed have vastly improved by the time that picture was taken, but it doesn't mean everybody automatically began using the most modern equipment and methods.  Some folks are prone to dragging their heels awhile.  Take this bunch for example.   

Hayface

When I securely hold something in my hand. my thumb goes on top of my fingers, not inside them; so there may indeed be something wrong with the man's left hand.

Next, I suspect that what's been called a cover tie may instead be a loop on the pant leg through which the mystery object is further secured.

I also suspect that the bottom of the stock and the buttplate have not been damaged; rather that area of the photo or the plate from which it was printed has.

Last couldn't the "thing" above his hat just be the blurred image of a bird?

Bill Lawrence