FSS IS300 attachment in MW4
The FSS IS300 is a muzzle attachment (“Suppressor”) that community sites list for 5 weapons: Han 86, M4, Hyeon Burst, Axion, and FiNN LMG. CODMunity lists a stat change on 5 of them; the largest is damage range +18% on the Han 86 (better). It is in 15 popular builds that CODMunity lists.
Community-reportedDMZ Codex, DMZ Radar, wzranked, ggranked, and CODMunity, read . Unverified, not Activision data.
Weapons that can equip the FSS IS300
Activision publishes no compatibility list; 5 community sources report these 5 weapons. DMZ Codex reports weapon level 4 on the M4.
| Weapon | Class | Weapon level | Stats with a listed change |
|---|---|---|---|
| Han 86 | Assault Rifle | damage range (large, better), bullet velocity (large, better), ADS idle sway (large, worse), ADS gun bob (large, worse), ADS speed (moderate, worse), ADS out speed (moderate, worse), vertical recoil (small, better), and horizontal recoil (small, better), and 7 more | |
| M4 | Assault Rifle | 4 | bullet velocity (large, better), damage range (large, better), ADS idle sway (large, worse), ADS gun bob (large, worse), ADS speed (moderate, worse), ADS out speed (moderate, worse), vertical recoil (small, better), and horizontal recoil (small, better), and 7 more |
| Hyeon Burst | Assault Rifle | damage range (large, better), bullet velocity (large, better), ADS idle sway (large, worse), ADS gun bob (large, worse), ADS speed (moderate, worse), ADS out speed (moderate, worse), vertical recoil (small, better), and horizontal recoil (small, better), and 7 more | |
| Axion | Assault Rifle | bullet velocity (large, better), damage range (large, better), ADS idle sway (large, worse), ADS gun bob (large, worse), ADS speed (moderate, worse), ADS out speed (moderate, worse), vertical recoil (small, better), and horizontal recoil (small, better), and 7 more | |
| FiNN LMG | LMG | bullet velocity (large, better), ADS idle sway (large, worse), ADS gun bob (large, worse), damage range (large, better), ADS speed (moderate, worse), ADS out speed (moderate, worse), vertical recoil (small, better), and horizontal recoil (small, better), and 7 more |
What the FSS IS300 changes
Percent changes are relative to the base value with nothing attached (CODMunity, read November 4, 2026).
| Weapon | Stat | Base | With it | Change |
|---|---|---|---|---|
| Han 86 | Damage range | 100% | 118% | +18% (better) |
| Bullet velocity | 615 m/s | 713 m/s | +16% (better) | |
| ADS speed | 250 ms | 280 ms | +12% (worse) | |
| Vertical recoil | 41.9 | 39.4 | −6% (better) | |
| Horizontal recoil | 11.2 | 10.5 | −6% (better) | |
| Movement speed | 4.67 m/s | 4.58 m/s | −2% (worse) | |
| ADS movement speed | 2.47 m/s | 2.42 m/s | −2% (worse) | |
| M4 | Bullet velocity | 590 m/s | 684 m/s | +16% (better) |
| Damage range | 100% | 116% | +16% (better) | |
| ADS speed | 240 ms | 271 ms | +13% (worse) | |
| Vertical recoil | 40.6 | 38.2 | −6% (better) | |
| Horizontal recoil | 17.1 | 16.1 | −6% (better) | |
| Movement speed | 4.70 m/s | 4.61 m/s | −2% (worse) | |
| ADS movement speed | 2.51 m/s | 2.46 m/s | −2% (worse) | |
| Hyeon Burst | Damage range | 100% | 118% | +18% (better) |
| Bullet velocity | 775 m/s | 899 m/s | +16% (better) | |
| ADS speed | 275 ms | 305 ms | +11% (worse) | |
| Vertical recoil | 38.3 | 36.0 | −6% (better) | |
| Horizontal recoil | 16.4 | 15.4 | −6% (better) | |
| Movement speed | 4.58 m/s | 4.49 m/s | −2% (worse) | |
| ADS movement speed | 2.36 m/s | 2.31 m/s | −2% (worse) | |
| Axion | Bullet velocity | 400 m/s | 464 m/s | +16% (better) |
| Damage range | 100% | 116% | +16% (better) | |
| ADS speed | 260 ms | 291 ms | +12% (worse) | |
| Vertical recoil | 48.9 | 46.0 | −6% (better) | |
| Horizontal recoil | 13.7 | 12.9 | −6% (better) | |
| Movement speed | 4.62 m/s | 4.53 m/s | −2% (worse) | |
| ADS movement speed | 2.41 m/s | 2.36 m/s | −2% (worse) | |
| FiNN LMG | Bullet velocity | 710 m/s | 824 m/s | +16% (better) |
| Damage range | 100% | 115% | +15% (better) | |
| ADS speed | 400 ms | 432 ms | +8% (worse) | |
| Vertical recoil | 49.0 | 46.1 | −6% (better) | |
| Horizontal recoil | 17.3 | 16.3 | −6% (better) | |
| Movement speed | 4.38 m/s | 4.29 m/s | −2% (worse) | |
| ADS movement speed | 2.03 m/s | 1.99 m/s | −2% (worse) |
Smaller changes are left out of the table: 8 other stats on the Han 86, 8 other stats on the M4, 8 other stats on the Hyeon Burst, 8 other stats on the Axion, and 8 other stats on the FiNN LMG.
Changes across weapons
The stats it changes on 5 weapons, with the lowest and highest change.
| Stat | Weapons | Lowest change | Highest change | Verdicts |
|---|---|---|---|---|
| Damage range | 5 | +15% | +18% | 5 better, 0 worse |
| Bullet velocity | 5 | +16% | +16% | 5 better, 0 worse |
| ADS speed | 5 | +8% | +13% | 0 better, 5 worse |
| Horizontal recoil | 5 | −6% | −6% | 5 better, 0 worse |
| Vertical recoil | 5 | −6% | −6% | 5 better, 0 worse |
| ADS movement speed | 5 | −2% | −2% | 0 better, 5 worse |
| Movement speed | 5 | −2% | −2% | 0 better, 5 worse |
| ADS gun bob | 5 | +15% | +15% | 0 better, 5 worse |
| ADS idle sway | 5 | +15% | +15% | 0 better, 5 worse |
| ADS out speed | 5 | +8% | +9% | 0 better, 5 worse |
| Horizontal gun kick | 5 | −6% | −6% | 5 better, 0 worse |
| Vertical gun kick | 5 | −6% | −6% | 5 better, 0 worse |
| Crouch movement speed | 5 | −2% | −2% | 0 better, 5 worse |
| Firing movement speed | 5 | −2% | −2% | 0 better, 5 worse |
| Strafe speed | 5 | −2% | −2% | 0 better, 5 worse |
How it ranks among muzzle attachments
Its largest change on each weapon, compared with the other muzzle attachments the source lists that stat for.
- Han 86: its large damage range change (better) is the best of 2 muzzle attachments.
- M4: its large bullet velocity change (better) is the only one listed.
- Hyeon Burst: its large damage range change (better) is the best of 3 muzzle attachments.
- Axion: its large bullet velocity change (better) is the only one listed.
- FiNN LMG: its large bullet velocity change (better) is the weakest of 2 muzzle attachments.
Pros and cons the sources list
Text from the community sources, without numbers.
Pros
- Pro: Sound suppression
- Pro: Muzzle velocity
- Pro: Damage range
- Pro: ADS recoil control
Cons
- Con: Aiming and movement speed
- Con: Gun bob and idle sway while aiming
Popular builds that use the FSS IS300
CODMunity lists 15 popular builds that use it: 5 for Multiplayer and 10 for DMZ. The styles are Apex Attachment, Mobility, Versatile, and Long Range. The same builds also use magazine, rear grip, laser, ammunition, stock, barrel, underbarrel, and optic attachments.
| Weapon | Mode and style | Tier | Other attachments | Builder |
|---|---|---|---|---|
| Han 86 | Multiplayer, Apex Attachment with Apex Attachment | Viable | Magazine: 45 Round Mag, Rear Grip: FTAC Griplord 80, Laser: XRK Clutch-LS, and Ammunition: 5.56 NATO Overpressured | Open in the builder: Han 86, Apex Attachment |
| M4 | Multiplayer, Mobility | Meta | Magazine: 45 Round Mag, Rear Grip: Schlager STB Grip, Stock: No Stock, and Laser: SZ Gen.6 PEQ | Open in the builder: M4, Mobility |
| Hyeon Burst | Multiplayer, Versatile with Apex Attachment | Absolute meta | Barrel: Mugi Ingoem 559mm, Underbarrel: FSS Fireline Grip, Stock: HVY-80 Stockpad, and Laser: SA LAZ-500 | Open in the builder: Hyeon Burst, Versatile |
| Hyeon Burst | Multiplayer, Mobility | Very good | Magazine: 40 Round Mag, Rear Grip: HYN-Meipeul, Stock: Mugi BAL-202 Stock, and Laser: SZ Gen.6 PEQ | Open in the builder: Hyeon Burst, Mobility |
| Axion | Multiplayer, Apex Attachment with Apex Attachment | Viable | Barrel: XRK 09-RTAC Pro, Magazine: 100 Round Drum, and Ammunition: .300 BLK Overpressured | Open in the builder: Axion, Apex Attachment |
| Han 86 | DMZ, Apex Attachment with Apex Attachment | Not tiered | Underbarrel: FSS Fireline Grip, Magazine: 60 Round Drum, Rear Grip: FTAC Griplord 80, and Laser: Schlager VISIV-5 | Open in the builder: Han 86, Apex Attachment |
| Han 86 | DMZ, Long Range | Not tiered | Optic: KV Corsac Holo, Barrel: SA H86 465mm, Magazine: 60 Round Drum, and Stock: FR4 Retractable Stock | Open in the builder: Han 86, Long Range |
| M4 | DMZ, Apex Attachment with Apex Attachment | Not tiered | Optic: ZLR Type C, Underbarrel: Hurricane Grip, Rear Grip: Schlager STB Grip, and Stock: No Stock | Open in the builder: M4, Apex Attachment |
| M4 | DMZ, Long Range | Not tiered | Optic: KV Corsac Holo, Barrel: 18" LE Crosswind, Underbarrel: FSS Fireline Grip, and Magazine: 60 Round Drum | Open in the builder: M4, Long Range |
| Hyeon Burst | DMZ, Long Range with Apex Attachment | Not tiered | Optic: KV Corsac Holo, Barrel: Mugi Seungri-0P 609mm, Underbarrel: FSS Fireline Grip, and Magazine: 60 Round Drum Mag | Open in the builder: Hyeon Burst, Long Range |
| Hyeon Burst | DMZ, Long Range | Not tiered | Optic: KV Corsac Holo, Barrel: Mugi Ingoem 559mm, Magazine: 60 Round Drum Mag, and Rear Grip: HYN-Meipeul | Open in the builder: Hyeon Burst, Long Range |
| Axion | DMZ, Apex Attachment with Apex Attachment | Not tiered | Barrel: XRK 09-RTAC Pro, Magazine: 100 Round Drum, and Ammunition: .300 BLK Overpressured | Open in the builder: Axion, Apex Attachment |
| Axion | DMZ, Long Range | Not tiered | Optic: KV Corsac Holo, Barrel: SA DMN-L 30", Underbarrel: FSS Fireline Grip, and Magazine: 100 Round Drum | Open in the builder: Axion, Long Range |
| FiNN LMG | DMZ, Long Range | Not tiered | Optic: KV Corsac Holo, Barrel: TT Seongun 508mm, Magazine: 150 Round Box Mag, and Stock: Hanbit Tech50 Gen.5 | Open in the builder: FiNN LMG, Long Range |
| FiNN LMG | DMZ, Apex Attachment with Apex Attachment | Not tiered | Optic: KV Corsac Holo, Barrel: TA N-VCX 18", Magazine: 150 Round Box Mag, and Rear Grip: FTAC R7 Wrap | Open in the builder: FiNN LMG, Apex Attachment |
Builds are community-reported and unverified.
Frequently asked questions
What does the FSS IS300 do in MW4?
CODMunity lists 75 stat changes for it across 5 weapons: 30 better and 45 worse. The largest is damage range +18% on the Han 86 (better).
Which weapons can use the FSS IS300?
Community sites list Han 86, M4, Hyeon Burst, Axion, and FiNN LMG. Activision has not published a compatibility list.
Is the FSS IS300 in a popular build?
Yes. CODMunity lists it in 15 popular builds, on Han 86, M4, Hyeon Burst, Axion, and FiNN LMG.