At the Snowchants Hunting Ground you can test your skills in two different trials: Control and Onslaught. You won’t get access to these trials until around mid-way through the DLC, but the idea is to complete the trial within a set time-limit.
For Control you need to be using the Stormslinger that you should have received from Ourea at the end of ‘The Shaman’s Path’ quest. To complete the trial in the fastest time, you should aim to make as many consecutive shots as possible on the Watchers and Scrappers. This will increase your damage output when it’s time to take on the Ravager. You have to take out 6 machines first, and the Ravager last.
Switch to the Blast Sling when fighting the Ravager, then finish it off with Stormslinger. Make sure to have some good Handling modifications attached to the Stormslinger to make it charge and fire much faster than usual.
This technique should help you to complete the trial in anywhere under 3 minutes. If you fail, or if you don’t get a time that you like, you can continue to go back and try again.