Wall weapons: Trench (obviously), Kar98k (Pack a Punch needed to be good)

Box weapons: Raygun (on early - mid game, also a must for getting Pack a Punch unlocked) Panzerschreck (same as raygun, an alternative for getting Pack a Punch), M1919 browning (Medium - High fire rate with good damage and lots of ammo), Saiga 12 (Basically auto shotgun with high fire rate and damage)

Note: This is just my opinion

Thanks!

Here's my loadout:

Walther (Pap required), Ray gun(Pap required, only for boss killing), and kar99/trench shotgun/saiga(All pap required)

I suggest getting the Walther because it is a consistent 1sk to the head until up to rounds 30 and whatnot.

The raygun gets progressively worse as the rounds go on and it's useful to have on standby for killing the boss or reviving teammates when you need splash damage, I rarely use it though because it can also splash you and get you killed really easily.

Kar98 1sk to the head really well and has overall better mobility and is more malleable than the ptrs, not to mention it's literally 200 points + the pap fee.

Trench shotgun is moreover the same reason as the kar98, good headshot damage, good for training zombies in the speed cola room, also a wall gun.

The Saiga is self explanatory, however putting a Jtek on it is debatable as ammo consumption is already really high by default. The papped Saiga is amazing at crowd control and is really good for killing the boss as well.

Weapon slots:

I put the walther and ray gun in the first two slots in the case thatI get downed, those two guns are relatively rare (if you don't get the garanteed ray gun on round 10) and the third slot guns will get lost if you go down, which is why I mostly use wall guns for them.

Early round:

The first thing you should prioritise if you are not doing glitches is the bowing knife, huge radius and 1sk up to round 11, very good for farming the crucial early game points, the next thing you should get is perks, if you have a bigger lobby you might want to get the mp40 or the thompson because overall point dispersion will be lower. You want to try get all your perks before pack a punch is opened up and the only gun you should get is the ray gun from the box on round 10. That isn't to say you should use the ray gun though because the bowing knife is literally enough to hard carry. Even on round 12 the bowing knife is only a 2 shot and it's fine if you dont have a gun yet.

Mp40: The mp40 is one of the best early game wall guns, the rate of fire is able to make sure you don't eat up ammo reserves to quick and the headshot damage is really good for something cheaper than the thompson.

Thompson: The thompson is also a great wall gun because it's located in the training room (speed cola room). It has a higher rate of fire and means you can get easier kills but ammo consumption will be higher.

For early rounds I suggest the loadout: mp40, ray gun, and the thompson, in that order.

If you play well and train zombies you can easily reach rounds 30+