Find some place that has elk that you cannot hunt, and practice on them.
Buddy of mine was in school in Calgary, used the ones at the wildlife park/zoo thing there.
Ended up at a Christmas do via his Missus, and ended up talking to their keeper. Guy said "Strangest thing, for a couple years, these guys have been living together and calm, but this fall they started kicking the living hell out of each other!"
Same guy, ex infantry, had been in a couple running gunfights in the city streets in the former Czech Republic, said it was the first time in a long time, he was scared, when a big bull came in through the trees like a train wreck, as he said "To kill me!"
Seriously, find a place with elk that you can see from enough distance, and see how they react to your calls, or if they do.