I use a call made by primos the name of it is "Imaka daBull Crazy" This call is amazing!
It has never let me down. I have always been able to call at least one bull in, whenever I go out. One of the guides I work for as some diaphram calls but he doesint have very many succes stories with it. I would highly reccomend the Imaka daBull crazy call.
The elk in my avatar, I called in within ten minutes of my hunt, Him and another bull came chargin over the hill.