If you get a chance to go to Rocky Jacobsons "Elk College", it is well worth it. You must tell a story.... Bone has great advice call less and listen, it will tell you what you need. I try to find a good spot, do some light cow/calf calls for about 2 minutes, then a easy locater bugle. If I get a responce... then its time to get the bull going. Depending on the responce. Everytime I hear a primos bugle, I laugh and move to anoher area. Sounds like a guy on a flute.... I prefer diaghrams, and the Bugling bull external cow call, but use the diaghram calls for most everything except the extreme estrus calling.