If you know there is a responsive elk that is willing to talk back, I wouldn't bugle anymore and switch right to cow calls. I might not bugle at all. I generally cow call for at least the first 15 minutes of my set. (not 15 straight minutes). Remember a bull is looking for love and not a fight. If he already has his cow's the only thing a bugle means is he could get his butt stomped and loose all his cow's. On the other hand more cow's mean's more love. He would rather lead his cow's away from the other bull 9 times out of 10. I would go back and leave the bugle in the truck. Also don't be to quite when calling. A heard of cow's brakes twig's and bump's rock's so try to sound like a few elk. Snap some twig's and such every once and a while to make it sound like some elk moving around. You might pick up a satelite bull this way trying to sneak some trim from the heard bull.