Hephaestus x GHK AMD-65 GBB: specs, joules & FPS

Complete specs Hephaestus CO2

Hephaestus x GHK AMD-65 GBB, CO2: 1.31 J, 375 FPS, 3,250 g, 50 rounds. Full specs from the official source, with FPS for every BB weight.

Power

Energy · computed1.31 J
Velocity375 FPS114 m/s

Above Italy's 1 J limit

Italian shops sell versions tuned below 1 J: ask the shop which version they ship.

Energy computed from the velocity with 0.20 g BBs, the standard weight manufacturers and shops use to measure FPS.

For information only, based on the source's data for this version. Not legal advice: always check current local law and the version the shop sells.

Technical specifications

BrandHephaestus
Modelx GHK AMD-65 GBB
CategoryAssault rifles & carbines
Power sourceCO2
PlatformAK SERIES
Weight3,250 g
Length850 mm
Magazine50 rounds
Hop-upAdjustable

Weighs 3,250 g: heavier than 77% of CO2 replicas in the same category in the database (65 with weight).

Similar alternatives

Replicas of the same type and category that stay within the Italian 1 J limit.

ReplicaEnergyFPSWeight
GHK AK74 GBBR0.95 J3203,460 g
VIVA Arms Mosin Nagant M44 Carbine (Real Wood CO2 Version)0.95 J3203,760 g
GHK AKS74M GBBR (Folding Stock)1.34 J3803,210 g
GHK AK105 GBBR1.27 J3703,190 g
GHK AK105 V3 GBBR (GHK AK V3 GBB System)1.34 J3803,350 g

Velocity with different BB weights

At the same energy, heavier BBs leave the barrel slower. Expected velocity with the most common weights:

BB weightFPSm/s
0.20 g375114
0.25 g335102
0.28 g31797
0.30 g30693
0.32 g29690
0.36 g28085
0.40 g26581

Theoretical calculation at constant energy (1.31 J). Real-world values can differ slightly with hop-up and replica.

Try other values in the joule ↔ FPS converter →

Data source

The values on this page come from the product page of the shop redwolfairsoft.com, checked on 2026-11-07. The manufacturer does not publish full specs: values may refer to the version that shop sells.

Shop product page ↗ redwolfairsoft.com

Spotted a wrong or missing value? Let us know.