Umarex HK33 GBB (by VFC): specs, joules & FPS

Complete specs Umarex GBB (gas blowback)

Umarex HK33 GBB (by VFC): 1.14 J, 350 FPS, 4,210 g, 30 rounds. Full specs from the official source, with FPS for every BB weight.

Power

Energy · computed1.14 J
Velocity350 FPS107 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

BrandUmarex
ModelHK33 GBB (by VFC)
CategoryAssault rifles & carbines
Power sourceGBB (gas blowback)
PlatformG3 SERIES
Weight4,210 g
Length1,027 mm
Magazine30 rounds
Hop-upAdjustable

Weighs 4,210 g: heavier than 97% of GBB replicas in the same category in the database (314 with weight).

Similar alternatives

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

ReplicaEnergyFPSWeight
VFC HK53 GBB1 J3283,200 g
Tokyo Marui CQBR Block 1 GBB0.95 J3203,110 g
Novritsch SSQ22 Gen2 GBB1 J3281,800 g
Tokyo Marui M4A1 MWS0.95 J3202,970 g
Cybergun Thompson M1A1 GBBR (by WE)0.98 J3252,690 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 g350107
0.25 g31395
0.28 g29690
0.30 g28687
0.32 g27784
0.36 g26180
0.40 g24775

Theoretical calculation at constant energy (1.14 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.

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