Mk4 Mod 0
| Factions | Weapon | Icon | Classes | Ammo |
|---|---|---|---|---|
 US |
 Mk4 Mod 0 |
 |
 Assault |
20+1 / 80 |
| Damage Base | Headshot × | Chest × | Stomach × | Leg × | Arm × | Bayonet | Rifle Grenades | Reload Speed | |
|---|---|---|---|---|---|---|---|---|---|
| Partial | Empty | ||||||||
| 35 | ×2.5 = 87.5 | ×1.2 = 42 | ×1.15 = 40.25 | ×0.8 = 28 | ×0.75 = 26.25 | NO | NO | 2.366 Seconds | 3.166 Seconds |
| Designation | Weapon Type | Fire Modes | Fire Rate | Bullet Spread ° | Range Modifier | Muzzle Velocity | Projectile weight | Weight |
|---|---|---|---|---|---|---|---|---|
| Mk4 Mod 0 | Suppressed Assault Rifle |
Auto+Semi | 750 RPM | 7.02° & 1° ADS | 0.950 | 960 m/s | 12.3 g (189.81 gr) | 3.89 kg (8.57 lbs) |
| Full name | Caliber | Place of Origin | Date | Manufacturer | Barrel Length | Total Length | Weapon Script Name |
|---|---|---|---|---|---|---|---|
| FN | 5.56mm | USA | 1967? | Colt | 20 in (508 mm) +Suppressor |
in ( mm) | weapon_mk4mod0 |
The Mk 4 Mod 0 is a Navy SEAL–modified variant of the M16A1 optimized for maritime and amphibious operations during the Vietnam War. It is best known for corrosion-resistant internal/external treatments and water-drain features intended to keep the rifle functional after submersion, along with SEAL-oriented accessories such as a blast suppressor.
HISTORY
Navy SEAL teams in Vietnam employed specialized small arms tailored to coastal, riverine, and amphibious missions. One such weapon was the **Mk 4 Mod 0**, a modified M16A1 pattern configured to better tolerate repeated exposure to saltwater, mud, and full submersion—conditions common to SEAL operations. The modifications described in period/historical writeups emphasize corrosion protection and practical “wet gun” reliability improvements, addressing problems that could otherwise stop a rifle after exiting the water.
Accounts describing the Mk 4 Mod 0 note that key operating components were treated with corrosion-resistant coatings (including Kal-Gard) and that drainage provisions were added (such as a small hole in the buffer assembly and drain paths) to help clear water from the stock/receiver area. Sources also describe SEAL use of a blast suppressor (often referenced as a Mk 2 Mod 0 suppressor) intended to reduce signature and improve water drainage compared to other devices, while still permitting semi-automatic and automatic fire—supporting the SEAL need for a compact, reliable rifle during covert maritime missions.
Sources
- https://hamptonroadsnavalmuseum.blogspot.com/2020/01/the-right-tools-for-job-seal-firearms.html “The Right Tools for the Job: SEAL Firearms in Vietnam” | Hampton Roads Naval Museum (blog)
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Mk 4 Mod 0 (SEAL-modified M16A1). -
Mk 4 Mod 0 (example image). -
Mk 4 Mod 0 (example image).
