Inner Barrel Prometheus EG 6.03 AA-12/SCAR/HK417/ M733/Thompson/MC+(Plus) 300 mm

The Prometheus EG inner barrel for the AA-12, SCAR, HK417, M733, Thompson and MC+(Plus) is designed as a direct replacement for the original inner barrel. Where the standard barrel often falls short in terms of accuracy, this Prometheus version provides better air seal and allows hop-up function to work more effectively. If you also use quality BBs, you'll get the maximum performance from the barrel.

The material is a deliberate choice: stainless steel is stiffer than brass or aluminium — the two materials most inner barrels are made from — and therefore offers greater resistance to deformation under rough use. Moreover, stainless steel has lower thermal expansion. If you fire many BBs in quick succession, the barrel heats up, but the effect on accuracy remains significantly smaller with stainless steel than with common alternatives.

Besides the material choice, the dimensions play a major role in performance. The inner diameter is 6.03 mm with a tolerance of only +/- 0.01 mm, the outer diameter is 8.5 mm, and the finish is executed at a high level. At the muzzle end, the barrel tapers slightly — this prevents instability from an abrupt pressure drop and instead provides a gradual and uniform pressure release. A solid upgrade for those wanting more consistency from their replica.