I hesitate to post but..... No experience with the 143 eldx on elk, only 2 deer....but I'm not sure I'd want to use that bullet for elk. Both bucks died but I'm a little skeptical on the bullet's performance. Again, only a sample of two and neither were perfect broadside shots. Others seem to have had great performance so it's only my experience.....I'll probably try it again on deer just because I'm so curious and want it to work.