Iron Brigade

You need to equip 2 items on your marine and then play a mission with them -

Psi Goggles - Completing the Emplacement Kills challenge
Raz Sweater - Completing the Scrap Collection challenge

For the Emplacement Kills Challenge you'll need 2500 kills using Emplacements (turrets, mines etc.) and for the scrap collection Challenge you'll need 25000 Scrap. After that the two items should be on your equipment list. you can check your progress by hitting start when youre on the ship, clicking challenges then right bumper over for personal challenges.

(scrap from collection emplacements also count. if you do the one before the last level in africa, sink hole think its called, you can end up with 1600-1700 scrap each time you beat it, plus Volcano is another good map for farming but it takes longer)

A great place to farm the scrap/emplacement kills is on the last level, Farnsworth.

My strategy was thus -
Take an engineering chassis with a mine layer, machine gun turret, collection turret and a healing turret. When you start the level, immediately turn around an put down the healing turret - this is your home base. From there put a collection chassis directly in front of it, as close as you can. Branching to the right and to the left alternate collection turrets and machine gun turrets on the periphery, outside of Vlad's laser's range. Also put a collection turret at the edge of both docks, also outside of laser range. Fully upgrade as you go. Once you have a few upgraded, go ahead and damage Vlad enough to get him to the third and final phase. Now go put a mine turret on either side by the spawn points. Once everything is upgraded fully, go back to the healing turret (home base), plug in your controller and go grab a beer. You should get about 15 hundred scrap every ten minutes, with no work on your side. With this strategy, I knocked out the required kills for the Razputin suit in about an hour.

If you vote negative, please let me know why!

Hello there! I have made a video showing you how to earn ~300 Emplacement kills and ~1,000 Scrap in about 15 minutes. Check it out and leave some feedback, thanks!

I've created a video walkthrough of what I feel is the easiest way to get this achievement, linked below.

Text summary:
I found it easiest to do this on Europe - Refinery. Taking a mine layer emplacement and a collector emplacement, I could very easily get 1400+ scrap and 120+ emplacement kills in 12 minutes. Place 3 mine layers in each of the lower center lanes, with 2 mine layers up on the higher outer lanes, and collector emplacements at each to pick up the scrap for you. It does require effort throughout the mission (as opposed to the other guide strategies suggesting the Vlad level where you can afk), but I feel it goes much faster on the kills and receives almost the same amount of scrap in the same time.

This is a more detailed version of SallyNasty's scrap collecting solution:
Solution for Razputin In Iron Brigade

For this achievement, you need to finish a mission, while wearing the following stuff:
Psi Goggles - Unlocked after 2500 emplacement kills
Raz Sweater - Unlocked after collecting 25.000 scrap

This solution helps with the scrap: after 10 minutes of preparation, it will automatically get you 1500 scraps per 10 minutes. TLDR? Here's a video:

This solution doesn't really work that well for emplacement kills (my average was 2 per minute :/). I used Dr Zleek's solution on Oasis for this one (300+ kills per 15 minute run): Solution for Razputin In Iron Brigade
Since you also collect scrap during these runs, do these emplacement kills first and then get back to this solution to collect the rest of the scrap.

Level
Pacific: Farnsworth (final boss fight)

Loadout
Chassis: Honeychurch
Legs: Whatever you like (I used Fortify)
Guns: Machine guns (fast enough to get the Knobs and enough range to hit Vlad)
Emplacements: Collector, Flak, Repair and Mines

Preparation
- Your Trench, Flaks and Repair station should stay out of Vlad's laser range
- Start with a collector in front of you (between the two green patches)
- Place a collector on the left and right side between the dock and the enemy spawn point
- Shoot the walking enemies that start spawning for some extra scrap
- Place the last two collectors inbetween the other three on the rocky outer ring

Now it is time to get some extra scrap
- Go back to the spawn point and start shooting Vlad in the red spot (you have to get close to acctually hit him)
- Once his health is down, start walking around, since his lightning will try to hit you and collect the scrap not picked up by your collectors
- If the lightning is over, you should have enough scrap to build a Flak and immediatly upgrade it to level 2 (40 + 60 scrap), build and upgrade the flak right in front of the palm trees left of the spawn point, it will take out all flying enemies

- Start upgrading the three collectors closest to the spawen point to their max
- If you run out of scrap, start shooting Vlad's red spots and destroy the first two (when he fires his laser, stay away as far as possible, since its area of effect reaches beyond the laser itself)
- After upgrading the three collectors, build a Repair station at the spawn point, as far away from Vlad as possible (this is where you will stay during the scrap collecting) and repair yourself to 100%
- Now shoot Vlad's last red spot and kill as many of the spawning Knobs as possible. They will probably kill your Flak, but try to keep them away from you Repair station (just stay away from it, as the Knobs first attack your Flaks and then your Trench)

- Rebuild and upgrade your Flak if needed and build and upgrade another one at the right side of the spawn point, in the corner between the sandbags and the rocks
- Now stand next to your repair station, plugin your controller and let the scrap collect. Most scrap comes from the lightning attacks, the damage caused by these attacks is minor and easily repaired by the Repair station.
- If you're standing still, the walking enemies should stay at their spawn point. If they attack you anyway, place a mine layer in front of their spawn point
- The safest way to finish the game and store your precious scrap, is to kill Vlad (quite hard with only the machine guns) or let yourself be killed.

There is a bit of an alternative way to getting this achievement.

First of all, the outfit does not change:
Psi Goggles - Completing the last personal Emplacement Kills challenge
Raz Sweater - Completing the last personal Scrap Collection challenge

You will need to wear both of articles of clothing when completing a mission to get the achievement.

Now the way that I got the achievement was actually from "Loot Boxes" that are dropped randomly by enemies, most often with Champion/Boss-type enemies. You may have noticed that if you replay an earlier mission the contents of the loot boxes will generally be the same. I would recommend that you play Survival Mode instead with three other friends to enjoy it to the fullest. One thing to note though is not everyone will get the same thing from the loot boxes, it is completely random.

For you non-DLC folks: The best setup that I can imagine is have two people with either the highest level "McGarry" or "Karlsson" chassis rocking out snipers/artillery, while the other two have the "Honeychurch" chassis for support capabilities equipped with grenade launchers (with magnet) or machine guns. Now make sure that you have every light turret, dampening pods (collection pods can help if you are playing with less than three people), and sniper and mine layers from the heavy turrets.

You will want to have one person covering each lane (front-center, back-left, and back-right) and one person behind the hospital. The person front-center and behind the hospital should be your sniper/artillery people. They should also be focusing more on upgrading all of the turrets rather than placing it themselves, although one of them can focus on flak turrets.

Each lane should have a mine layer to start off directly infront of the "portals" where the enemy comes out of, after it is fully upgraded you move onto a fully upgraded dampening pod and add a shotgun/machine gun turret. Then just focus on adding more of everything to these lanes. One of the back engineers need to place these items at the front-center lane as well. Flak turrets and sniper turrets should also be placed around the hospital. Sniper turrets need to be able to reach the side portals so that they can take out snipe tuners and help with the Volt Dropper.

Jacobs will be the most annoying enemy! Always focus on them first, they will begin spawning heavily around wave 15.

While all of this is based on luck, if you enjoy this game it is much better to do this than to grind it out on the Farnsworth level. I ended up doing that for an hour and only got half of the challenge done, then when my friend asked me to play survival I ended up getting the achievement shortly after. It took 10 games lasting until wave 10-30 to get both pieces, my friend didn't get any though.

If you need more help with survival, check it out on youtube. I'm not an expert at the game, or at survival so I'm sure they can help you out more than I can.

Also for those unaware: Survival mode gives you better gear as bonuses for completing every five waves. It is the same gear each time you complete the same number of waves, so you want to go as far as you can.