In case you haven't updated just yet, DICE has just released the first update for Battlefield 1. This update is around 766MB in size, however the team has not revealed yet its release notes.... Battlefield 1 - patch v1.02
Things I have noticed weird... When I get a new gun in the box and add to inventory, I can never find it again or use it in a round. Open game, black screen appears, then closes again to desktop.. At end of round in my progress page, the progress bar increases to show xp earned in round but then this disappears again like it took it away from progress.
You don't get new weapons from battlepacks, just skins. To equip them, customize the weapon ingame; if you have unlocked a skin, you should have an additional option below the bayonet.
They're skins not new guns, in the customize menu, you'll find them under visualization,unless you haven't unlocked that weapon.
I'm going to start the game tonight for the first time. Hopefully after this patch I will have a okay first time experience.
Patch notes https://forums.battlefield.com/en-us/discussion/44346/battlefield-1-update-10242016#latest