I am happy that this thread generated the comments that it did as it gave me a reason to more closely examine the inner working of the rifle. I am; however, going to have to reverse my statement that the nipple guard is retained by friction, it isn't. That pin in question transverses that side plate and terminates in a cam. The nipple guard is attached to the pin by the nut. when the nipple guard is swung forward off of the nipple the whole unit rotates and acts on a spring loaded pawl that is retained on the plate by the screw and pins that you see directly under the nipple bolster. I didn't get any photos of the mechanism as I am reluctant to try to remove the screws that retain the fore stock pieces. I would like to thank everyone who has or will participate in this thread as it has been a great learning event for me.
