Hiking and backpacking is strenous and will make you perspire. If you wear a shoulder holster it will be a vertical rig, and you will sweat on it, and rust can form if you do not oil it well and wipe it down when you stop. Plus, you will have the straps of your backpack over the straps of your shoulder holster. Not very comfy. You can try a $25 Hunter hip holster with a thumbsnap, but it can get heavy. I carry my 629 IN the backpack inside a Hunter flap holster. There is a lot of waist motion in hiking, and I figure that is one less strain I should add to my hiking day. Of course, you can buy an Uncle Mike's flap holster worn across your chest in a diagnonal draw. that is WAAY exposed, though.