Gunsmith – M4A1 is the USEC build that combines a suppressor and large magazine with a 3.8 kg weight limit. It is separate from Gunsmith Master – Part 9, which asks for a thermal-equipped M4A1 and a different attachment set.
Requirements
- This quest is only obtainable by USEC PMCs.
- Mechanic loyalty level 3.
Objectives
- Modify an M4A1 to comply with the given specifications
Weapon specifications
- 60 Durability
- 37 or greater ergonomics
- 300 or less recoil
- 800 or greater sighting range
- 3.8 kg or less in weight
- A magazine with a capacity of at least 60
- A silencer
How to complete the build
Use an M4A1 from Peacekeeper LL3 as the base for the example configuration. Choose one suitable magazine from the alternatives below rather than buying every magazine in the table.
Keep an eye on weight as you add the suppressor, optic and magazine. A weapon that meets the recoil requirement can still fail because it is too heavy.
Check the complete weapon in the inspection window before handing it over. The quest checkmark can be inconsistent even when a build qualifies, so a missing marker alone does not prove the weapon cannot be submitted.
Build screenshots
These screenshots show our earlier M4A1 setups. Use the current specifications above when checking your finished build.
Example parts and trader access
These parts form an example configuration. Follow any alternative-part choices in the table and check the assembled weapon against every required stat. LL refers to trader loyalty level.
| Component | Trader | Access |
|---|---|---|
| Magazine – You only need one of the below | ||
| AR-15 5.56×45 SureFire MAG5-60 STANAG 60-round magazine | Peacekeeper | LL3 (Barter) |
| OR | ||
| AR-15 5.56×45 Magpul PMAG D-60 STANAG 60-round magazine | Peacekeeper / Ref | LL4 (Barter) / LL4 |
| OR | ||
| AR-15 5.56×45 SureFire MAG5-100 STANAG 100-round magazine | Mechanic | LL4 |
| SIG Sauer ROMEO7 1×30 reflex sight (Prototype) | Skier | LL1 |
| AR-15 5.56×45 10.3 inch barrel | / Peacekeeper / Mechanic | LL2 (Barter) / LL3 / LL2 (Barter) |
| AR-15 Daniel Defense MK12 Low Profile Gas Block | Peacekeeper / Mechanic | LL2 / LL2 |
| AR-15 SureFire WarComp 5.56×45 flash hider | Skier | LL2 |
| SureFire SOCOM556-MINI MONSTER 5.56×45 sound suppressor | Skier / Mechanic | LL2 (Barter) / LL3 |
| AR-15 MFT BUS stock | Peacekeeper | LL2 |
Rewards
- +28,000 EXP
- Mechanic Rep +0.75
- 275,000 Roubles 288,750 Roubles with Intelligence Center Level 1 316,250 Roubles with Intelligence Center Level 2
For more of Mechanic’s weapon builds, see our Gunsmith Master – Part 2 and Gunsmith Master – Part 7 guides.
I keep on getting “Cannot install both 260mm AR-15 5.56×45 and MOE SL at the same time” error. Is there a way to get around this?
Weird, I tried replicating the same build… did not have that issue at all. I also used the default M4 from Peacekeeper.
I have the same problem, it says it can’t install both 260mm barrel and the MOE SL
Ohh wait there are two different MOE SL mods – only one works with the 260mm barrel FYI to other people! (it’s the greyish green one that works)
Didn’t work :(
It should be working unless they changed the quest requirement. I will make adjustments if necessary.
Didn’t work for me either
Hey Alex, thanks for your comment. I just rechecked the M4A1. It fully complies with the requirements. I also updated the article showing the picture. Are you sure your magazine is empty, or you have the right charging handle?
Hi, this does not work because the gun is too heavy. How did you get it under 3.8 kg?
Hey, have you checked if your magazine is empty?
I had to swap out the charging handle for the raptor, then take the foregrip and rail off and use an AFG.
My mag was empty as was my chamber.
I think they changed the weights of some of the items.
I will jump on it right now.
I just wanted to let you know that Gunsmith Part 4 is completely reworked. Let me know if you have any trouble.