When choosing your Sniper Rifle in Battlefield 1, definitely consider each rifles sweet spot range depending on your playstyle and average engagement range. If you like to play more aggressive, you'll probably want to choose a bolt action that has a sweet spot range that's better up close, and if you like to snipe from a distance you'll probably want to choose a rifle that has a sweet spot range meant for long distance.
Please note that not all bolt action rifles in Battlefield 1 have a sweet spot range, however some have stronger base stats. This is also something you'll want to consider when choosing the best bolt action sniper rifle for your playstyle.
As for gadgets in Battlefield 1, the flare gun is extremely useful, basically working just like the motion sensors in Battlefield 4, enabling you to see players on your minimap. Use these wisely and you'll have a significant advantage over enemy players! In the Battlefield 1 Beta we also had a variation that emitted a very bright light, and while I didn't find this very useful on Sinai Desert, being a more open map, this gadget could be very useful on tight, close quarters maps (think Operation Locker from Battlefield 4). Verdicts still out on K-Bullets however. They were very good in the Battlefield 1 Alpha, simply because you could disable a tank in one shot if you hit it in the track or the engine. However they weren't good at all against tank heavy armor in the Battlefield 1 Beta, and were really only useful against Armored Cars. So, hopefully they'll get a slight buff as far as damage against tanks.
Look for more Battlefield 1 Sniping Tips & Tricks after the full release of the game, including a full Battlefield 1 Scout Class Guide covering everything you need to know!
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