I'm a very average player with maybe 2 or 3 kills a game but wanted to say this.
If you are a great sniper then it's ok, but if you are not then please don't start shooting people from 200-300 yards away with your teammates right next to you. It may damage them and make them hide/retreat. However, by the time we reach them they heal and shield up. They now also know where our position/point of attack and are ready for us. It doesn't help the team, especially in the random queue.
Please let your teammates get some closer by pinging enemy position and then shoot, so we can take them down together by surprise. So many of snipers I encounter start shooting from far back before we can move in. Until we get there either two more squads are waiting or the team is entrenched into a good position.
If it is a repost, by bad. Encountered this in 12 out of last 15 rounds today.