I have a bark buster powered by a 3 HP briggs and straton engine. It used a chain drive too a cintrifical clutch. I really liked the thing but the cone was Alum with a harden steel nose cone to start the screw held in place with a roll pin. that Alum part broke after about 3 years of hard work so I bought a new one. that one also broke after about 3 years.
I was not able to find a 3d one to buy so the machine sets in my pole barn waiting for me to say HEY and spend the money for a stickler cone and adapt it to the bark buster hub.
I found part of the trick to make the bark buster split better was to run the cone in close to the end. If a chunk did get stuck the clutch slipped and just shut the engine off then it was easy to use a pipe wrench to screw it backwards.
I liked it because I could take it to the woods where we were working, load it in the pick up all by my self and then put it on top of the load of wood alone also.
I do have a hydraulic spliter now but it isn't as handy. I also feel it is no safer than the bark buster with the clutch. My hydraulic will some times go into stubborn wood and when it finally pops will toss a chunk of wood several feet with force.
So if some one runs a cross a used stickler cone cheap yell at me.

Al