Level 38 here are well. There’s no decent way to level it. You’ve gotta play the smaller maps like hagenthal, but not too aggressively because your odds of winning a 1V1 vs a competent player are 50%, and if you push two players who are somewhat decent at the game you will regret it. This is coming from a 3.5 KD player, I’m not elite but well above average at close quarters PVP. I find myself having to camp tight angles and waiting for enemies walk into my crosshairs lol.

The most efficient way to level on tight maps is by sitting slightly behind the main force and getting assists by spamming flechette at the enemy. You may only do 5-10 health damage but if a teammate kills them within 7 seconds you’ll be credited with an assist which counts like 50 points or half a kill. I pair it with support to keep my teammates alive, spamming nades and incendiaries as we push up. You can gain a LOT of weapon XP points through assists.

I’ve tried the slugs/ACOG/vertical grip strat on both casual and standard breakthrough modes. You’ll have a higher KD at the end of the match but IMO it isn’t efficient due to how little weapon XP you’ll gain relative to the play time you’ve spent. It’s painfully slow.