building guns not working

@Reknat415 are you talking about melee weapons? The ones that are made of 5 puzzle pieces?

Those can only be unlocked via Battlepacks, so check the revisions regularly.

The French and Russian knives can only be unlocked by the special Battlepacks that you´ll get for finishing the Operations Campaign.

no no i know melee weapons are from battlepacks i mean normal firearms weapons 

@Reknat415 you don´t build normal weapons, that´s why I misunderstood that. Sorry.

So which weapons are you exactly talking about?

Do you own Premium or a single DLC as @eI-nombre already mentioned?

@Reknat415 As mentioned by @Ourumov13 if you provide us some examples of guns you are after to 'build' we can help you better.

There's a large variety of weapons available, and the ways to get them vary too.

There are Base game guns available to each and every player that owns the game at the start. For each class certain guns are availble from scratch. Others require warbonds to unlock (Buy) them. By progressing in multiplayer should earn sufficient warbonds by the time you hit overall rank 70 to unlock all guns and vehicle loadouts that are available, if not please refer to This topic created by @EA_Joker

Then there are some weapons, also available to all players who own the base game, but which are unlocked based on the class rank. You will need to hit class rank 10 to unlock these. Meaning there are 4 guns (1 for each class) you can unlock. And these guns each have a second variant which can be unlocked by completing a certain assignment.

Example; the Hellriegel 1915 Factory, unlocks by reach class rank 10 in assault. Then there's a variant called the Hellriegel 1915 efensive. To unlock this, you need to get 300 kills with the Hellriegel 1915 Factory, and 25 kills with AT Mine. The assignments per each of these class rank 10 gun variants can be viewed and tracked in the companion app.

Next there are guns that have been added with DLC's. These require you to own the DLC, either as standalone or via a Premium pass. All of these guns need to be unlocked via assignments as well. And again you can view and track the assignments for each of these via the companion app. And in the companion app you also can see the distinction between guns that are available to all players and those only available to Premium/DLC owners. Weapons available to all players are displayed in white, the weapons which are not are greyed out

Example; 

And by clicking on any of the weapons that require an assignmnet, such as the Farquhar-Hill Storm from above example, you will get the necessary info on that weapon. Showing you the DLC it belongs to, as well as the unlock requirements

Then there are the Melee weapons that you need to build from puzzle pieces which you can collect via the Battlepack system or the scrap exchange. You already stated you know how this works. So assuming that you are a Premium/DLC owner. I'll just briefly explain for anyone else reading this.

Via the battlepack system you have a chance to obtain puzzle pieces as a bonus item on top of the weapon skins you receive. Battlepacks can be bought with scraps. You earn those by logging in to the game, winning your first match of the day, or appearing on the round-end highlights. Or you can buy a puzzle piece with the scraps if it is featured in the scrap exchange of the current revision (requires a lot of scraps for 1 piece)

With these puzzle pieces you can build a new melee weapon. Each weapon requires 5 puzzle pieces. There are 2 of these available to Base game owners (Sawtooth Knife and Bartek Bludgeon), all others are again tied to Premium/DLC.

Furthermore there are some weapons which are only available to people who bought certain editions of the game. For example the Deluxe edition or Revolution edition would give you 3 packs that contain unique weapons; Red Baron Pack, Lawrence of Arabia Pack en Hellfighter Pack. In essence these are themed skins for base game weapons, but they do appear as a separate weapon variant on the companion app. And nowadays these should only appear when you own the edition/packs. This used to be different.

Example;

And then finally you will find in the companion app on your weapons list some Bolt Action rifles under the section Standard Issue Rifles. These are tied to the game mode called Standard Issue Rifles which was added in the December 2016 update, and you will need to play this game mode in order to use these. These are basically stripped down versions of scout rifles, so without scopes, magnification etc. to be used as primary weapon in this specific mode and you are forced to use these across all classes.

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I do not work for EA, I'm a gamer trying to help fellow gamers. :eahigh_file: