[Ron Wood]

The hold open is activated by the magazine. You can not cause the bolt to remain open if there is no magazine present. Insert an empty magazine and open the bolt and it will remain open if the hold open is working correctly. You may then remove the magazine and the bolt will remain open until you pull back slightly on the toggles to release it. Then, with the magazine still removed, if you hold the trigger while you slowly lower the toggle (never do this when loaded magazine is inserted!), you will close the bolt without cocking the firing pin. Therefore there is no strain on the firing pin spring and no danger of "dry firing" and possibly damaging the firing pin.