Definitely designed to fire something as it has a breech block and open barrel. Make sure that breech is dogged down before you fire it. Years ago i was firing a homemade cannon using a Hilti gun blank and the breech was not in place. Ended up with a whole bunch of shrapnel in my thumb from the brass casing. After 2 days of agony and a big bottle of scotch i finally surrendered and headed to the hospital. They had to open the thumb to the bone and remove some wicked chucks of brass from the bone. Have fun but be careful !!!!