Best M4 Loadout and Build in MW4 (Modern Warfare 4)
By Luke Setzer · Updated 8/24/2026
The best M4 loadout in the MW4 beta runs the FSS IS300 muzzle, FSS Fireline Grip underbarrel, Brace DX Grip rear grip, No Stock, and the SZ Gen.6 PEQ laser. Pair it with Ninja, Fast Hands and Battle Hardened. The M4 is the S-tier assault rifle and is available early, so it is the first gun worth building.
The M4 is the S-tier assault rifle in the Modern Warfare 4 beta: the easiest gun to pick up and beam with at range, and it is available early. Here is the best M4 loadout, the class to pair it with, and a beginner setup for before you unlock everything.
Best M4 loadout in the MW4 beta
- Muzzle: FSS IS300 (Level 4)
- Underbarrel: FSS Fireline Grip (Level 37)
- Rear Grip: Brace DX Grip (Level 10)
- Stock: No Stock (Level 57)
- Laser: SZ Gen.6 PEQ (Level 2)
Why this M4 build works
The muzzle and grips tighten the M4's recoil so it stays flat on longer bursts, while No Stock and the laser trade a little stability for faster aim and movement, so you can push and still hit your shots. It is a balanced beam build that suits nearly every map in Modern Warfare 4.
Best class and perks for the M4
Run the universal class: Perk 1 Ninja (Level 20), Perk 2 Fast Hands (Level 12), Perk 3 Battle Hardened (Level 28), with a Semtex lethal and a Flashbang tactical. Battle Hardened unlocks at level 28, so use Blood Rush or Scavenger until then.
Beginner M4 setup (before level 20)
Most of the best attachments unlock later, so while you climb: Muzzle FSS IS300 (Level 4), Optic Slimline Elite (Level 13), Stock PF1 Fixed (Level 14), Ammunition 5.56 NATO Overpressured (Level 3), with Quick Fix and Scavenger as your perks.
Remember: it is a beta
Expect Activision to buff and nerf guns, add weapons and drop new maps before the October 23 launch, so the M4 meta can shift. Treat this as the best M4 build right now.
Unlock the attachments fast
Some of these sit behind high levels, a big grind on the short beta clock. MW4 Beta Gun Leveling maxes the M4 and unlocks every attachment for you, MW4 Beta Bot Lobbies let you level fast yourself, and our guide on leveling guns fast covers the free methods.
More beta builds: the full MW4 beta best loadouts and classes, plus the ISO Nightshade, Kastov 762 and KG-7 Vulcan loadouts.
FAQ
What is the best M4 loadout in the MW4 beta?
FSS IS300 muzzle, FSS Fireline Grip underbarrel, Brace DX Grip rear grip, No Stock, and the SZ Gen.6 PEQ laser. It keeps the M4's recoil flat while adding mobility.
What level do the M4 attachments unlock?
The laser (SZ Gen.6 PEQ) is Level 2 and the muzzle (FSS IS300) is Level 4, but the underbarrel is Level 37 and the No Stock is Level 57, so the full build takes a grind past level 20.
What class should I run with the M4?
Ninja, Fast Hands and Battle Hardened, with a Semtex and a Flashbang. Battle Hardened unlocks at level 28, so use Blood Rush or Scavenger early.
Is the M4 good in the MW4 beta?
Yes, the M4 is the S-tier assault rifle in the beta and is available early, which makes it the first gun worth building.