The outer barrel is the rifle's visible barrel length. Change it and the rifle becomes a different platform — CQB to carbine to DMR with one swap.

On an airsoft rifle, the outer barrel is what the customer sees and what the inner barrel hides inside. It's a cosmetic and structural component — it provides the threading at the muzzle for a flash hider or suppressor, the housing for the inner barrel, and the visible length that defines whether the rifle reads as CQB, carbine, or DMR. Unlike the inner barrel, the outer barrel doesn't affect accuracy directly — but it does affect rifle balance, profile, and the muzzle device options available.

Standard lengths correspond to rifle archetypes. 7" / 10" CQB outer barrels make a rifle short, fast-handling, and indoor-orientated. 14.5" carbine is the iconic M4 length — the all-rounder. 16" mid-length sits between carbine and rifle — longer sight radius without DMR commitment. 18-20" DMR / sniper outer barrels are the long-barrel profile for marksman roles. Profile shapes include standard contoured, stepped (DD-pattern), bull barrel (cylindrical full-length), and fluted (vented for weight reduction).

Threading and material. Most M4-pattern outer barrels use 14mm CCW muzzle threading; AK-pattern outer barrels usually use 14mm CW. Aluminium outer barrels are the lightweight standard; steel outer barrels add weight and authenticity for milsim builds; forged carbon outer barrels (see OG Carbon) are the premium UK-made option for MTW builds. For the inner barrels that fit inside, flash hiders and suppressors that thread onto the muzzle, see the relevant collections.

💡 Titan Forge tip: Changing the outer barrel changes the rifle. A 14.5" M4 with a 7" outer barrel becomes a CQB rifle without needing to buy a new platform — same gearbox, same magazines, same training. Worth considering before buying a second rifle for a different role — an outer barrel swap is often the same cost as a quarter of the new rifle and produces a meaningfully different platform.