Early Contenders are hard to open. The hinge pin for the trigger guard/release lever is at the front of the part and gives little mechanical advantage. If the locking "bolts" on the barrel are tight fitting then one has to work at opening these frames. The next generation of Contenders moved the hinge rearward and are much easier to open, hence know as "easy open" Contenders. Early ones can be converted to this mode by the factory or by the custom shop as described in the above post. The current model, G-2 Contender, is quite easy to open. Most of my frames are now G-2 for that reason. As I approach middle age <VBG> my arthritis makes it harder for me to love my originals!