While this achievement says "Have at least one player shoot 100% from behind the arc (min 10 attempts)" , I found that to unlock it, one player must take all 10 shots, and make each shot count, instead of the team combining for 10 attempts and a player go something like 2-2 or 3-3 for a 100% shooting percentage.
Which makes this achievement seem more challenging than the 7 needed in NBA Live 14. Except the shooting mechanics are more user-friendly now. Adjust to sliders to 100% and use Steph Curry from Golden State in a Tip-Off match. I also changed the shot option from "Rating + Skill" to just "Rating" Get to the 3-point line and try not to get fancy by shooting off-dribble or face heavy defense and you should hit every shot no problem. If you miss one, just restart the game