CptCurl, those two hammer rifles are very nice examples of the this type rifle! I have a few hammer doubles, rifle, cape guns, and shotguns. Like everyone else who posted to this question, I have my own system for useing the double hammer gun/rifle. IMO, what ever works best for you is correct, FOR YOU!

I find there is a difference between how I use a shotgun,and how I use a double rifle. Mainly because they are much different weights. Shotguns being light can be cocked in just about any way you choose. They can be cocked like a single action pistol with the only support being the hands, while cocking. I don't have any that do not have rebounding hammers, so that simplifies my drill some! I think without rebounding hammers I would carry open, or unloaded. I don't trust the notch enough to hold the hammer that far away from the strikers. If it happened to fall it would fire, IMO, where a simple fall from the rebound notch would not!

I carry the rifles loaded, usually with a soft in the right, and a solid in the left, with the hammers down on rebound notch. When game is spotted,and it is decided the trophy is worthy, I start the stalk, hammers still in rebound. At the point where I intend to shoot, if standing, I place the butt stock between my upper right arm, and my chest. if sqawting, I place the rifle accross my upper legs. In both cases,the left hand slides up to the hammers, while my right hand is already there. With the thumbs of each hand, I cock both hammers similtaniously, as the left hand slides back onto the forend as I mount, and fire, the right barrel. If time allows, and I'm very close, I cock one barrel at a time, by holding the trigger for that barrel back till the hammer is all the way back, then release the trigger. This cocks the rifle in complete silence.

When a quick shot presents it's self, simply cock both hammers on the way to the full mount, with both thumbs, and fire! In this case there is not a need for silence, as much as speed of fireing the first shot!

I have tried the both hammers with the side of one hand, and it doesn't work for me, and an occasional missed cocking of one hammer has resulted in a barrel fireing.

Hope any of this helps, and while I've got your attention, if you have a need to sell one or both of those doubles you posted here let me know, I may have to put the old ranch in hock again!