8 Umarex Mp5 Gbb of 2026 For Proper Feeding and Fit

1

GoldenBall x Eagle 35 Round Gas Airsoft GBB Magazine for

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• ARS Mark

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  9.0
• Brand
  GoldenBall

Key specs2

Platform Compatibility

GHK and WA series gas blowback rifles

Internal Build

Combines a metal internal reservoir and valve structure with a lightweight polymer outer housing.

Pros & cons42

Pros

• High flow output valve delivers consistent gas release for blowback cycling
• Polymer outer housing reduces overall gear weight across multiple magazines
• Metal internal system provides structural rigidity under gas pressure
• 35-round capacity matches realistic gas blowback rifle specifications

Cons

• Engineered for GHK and WA series gas systems rather than Umarex MP5 receivers
• Will not seat or lock securely into Heckler & Koch MP5 magazine wells

2

HK Heckler & Koch MP5 6mm BB Rifle 200-Round Hi-Cap

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• ARS Mark

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  8.6
• Brand
  Umarex

Key specs2

Power System Type

Electric AEG only

Verified Gun Fit

• HK MP5 Competition Kit (model 2275052)
• HK MP5 SD6 airsoft rifle (model 2275053)
• HK MP5K airsoft rifle (model 2275055)

Pros & cons42

Pros

• Stamped steel outer shell matches factory HK firearm receiver construction
• 200-round capacity delivers high volume fire without frequent mag changes
• High strength polymer internals ensure smooth feeding for 6mm plastic BBs
• Fits HK MP5 Competition, SD6, and MP5K electric airsoft models

Cons

• Designed for electric AEGs and completely incompatible with GBB gas systems
• Lacks the internal gas reservoir and valves required to operate blowback rifles

3

Glock 19X Half Blowback 6mm BB Pistol Airsoft Gun Magazine,

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• ARS Mark

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  8.6
• Brand
  Elite Force

Key specs2

Magazine Capacity

14 rounds (6mm BBs)

Gun Compatibility

Manufactured for Glock 19X half blowback 6mm pistols and does not fit any MP5 receiver.

Pros & cons32

Pros

• Authentic Elite Force magazine engineered for Glock 19X airsoft pistols
• Compact profile fits easily into standard sidearm magazine pouches
• Feeds standard 6mm plastic airsoft BBs reliably

Cons

• Built strictly for Glock sidearms and cannot fit MP5 submachine guns
• 14-round capacity is inadequate for primary tactical rifle engagements

4

MetalTac Airsoft Speed Loader with Capacity of 100 Bbs

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• ARS Mark

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  8.4
• Brand
  MetalTac

Key specs2

Included Adapters

Includes gas magazine adapter

Physical Dimensions

• Length: 5.125 inches
• Width: 1.75 inches
• Height: 0.9 inches
• Weight: 0.12 pounds

Pros & cons42

Pros

• Bundled gas magazine adapter enables quick filling on narrow GBB feed lips
• Holds up to 100 rounds of 6mm BBs to refill multiple low-capacity magazines
• Compact 5.1-inch length fits cleanly inside tactical vest pouches or pockets
• Smooth plunge rod loads magazines roughly 20 times faster than by hand

Cons

• Lightweight plastic construction requires careful handling on hard surfaces
• 100-round BB reservoir empties quickly during high-volume shooting sessions

5

BOX OF 5x CYMA Airsoft 120-Round Mid Capacity Magazine for

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  8.4
• Brand
  CYMA

Key specs2

Fitment Warning

Manufacturer specifications state these do not fit HK receivers, and they lack gas valves for GBB use.

Pack Configuration

Box of 5 mid-cap magazines (120 rounds each)

Pros & cons32

Pros

• Five-magazine bundle equips an entire loadout without individual orders
• Mid-capacity 120-round design prevents BB rattling during tactical movement
• Spring-loaded feeding requires no manual winding wheel during gameplay

Cons

• Explicitly labeled not to fit HK receivers according to manufacturer data
• Built solely for electric AEGs and cannot function in gas blowback platforms

6

NcSTAR MDMP5V2 Mp5/Hk Claw Scope Mount/Gen Ii

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• ARS Mark

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  8.0
• Brand
  NcSTAR

Key specs2

Receiver Attachment

Mounts directly to HK claw mount lugs on stamped receivers including MP5, SP89, HK91, HK93, and HK94.

Rail Standard

Picatinny top rail

Pros & cons42

Pros

• Clamps securely to stamped receiver lugs on MP5 and SP89 platforms
• Provides a standard top Picatinny rail for red dots and optical sights
• Lightweight 0.156-pound design prevents awkward top-heavy gun balance
• Gen II design also mounts to CETME and HK 90 series stamped receivers

Cons

• Requires HK-spec receiver lugs and will not secure to non-spec airsoft bodies
• Clamping screws must be monitored to ensure they remain tight under recoil

7

Umarex HK Heckler & Koch USP GBB Blowback 6mm BB

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• ARS Mark

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  8.0
• Brand
  Umarex

Key specs2

Dedicated Pistol Fit

• HK USP Compact GBB (model 2275013)
• HK USP Compact GBB (model 2275004)

Propellant System

Features an internal green gas reservoir for blowback operation, with green gas sold separately.

Pros & cons32

Pros

• HK licensed design ensures exact fitment on HK USP Compact GBB pistols
• Internal green gas reservoir powers crisp blowback slide cycling
• 22-round capacity offers realistic sidearm capacity for 6mm airsoft BBs

Cons

• Designed strictly for USP Compact pistols and cannot seat in an MP5 rifle
• Green gas propellant must be purchased separately to charge the magazine

8

Elite Force Walther PPQ GBB 6mm BB Pistol Airsoft Gun

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• ARS Mark

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  7.2
• Brand
  Elite Force

Key specs2

Extended BB Capacity

45 rounds (6mm BBs)

Platform Compatibility

Designed specifically for the Walther PPQ gas blowback pistol platform and will not mount to an MP5.

Pros & cons32

Pros

• Extended 45-round capacity delivers superior firepower for gas blowback setups
• Engineered specifically for Elite Force Walther PPQ GBB airsoft pistols
• Gas blowback valve mechanism supports rapid semi-automatic cycling

Cons

• Built exclusively for Walther PPQ pistols and cannot fit MP5 platforms
• Extended base adds extra length that may not fit standard pistol mag pouches

Last update on 2026-10-07 / Affiliate links / Images, Product Titles, and Product Highlights from Amazon Product Advertising API

Does an MP5 AEG magazine work in a GBB rifle?

No. Electric AEG magazines do not have the internal gas reservoirs or release valves required to cycle a gas blowback bolt. High-capacity AEG magazines, such as the HK 200-round magazine (part number 2275054) built for the 2275052 MP5 Competition Kit or 2275053 SD6, rely entirely on internal springs for electric gearboxes. Inserting an electric magazine into a GBB receiver leaves the rifle completely unable to fire. Always confirm that your magazine contains internal gas valves and GBB feed lips before purchasing.

How do you mount a Picatinny optic to an HK MP5 receiver?

Clamp a dedicated claw rail directly onto the stamped receiver lugs. The NcSTAR MDMP5V2 Gen II claw scope mount attaches directly to the top of HK-spec stamped receivers, including the MP5, SP89, and HK91, HK93, or HK94 platforms. This provides a secure top Picatinny rail that prevents your scope or dot sight from shifting during shooting. Always verify that your receiver matches original HK stamped specifications so the claw brackets lock securely into place.

Can CYMA MP5 magazines fit HK airsoft platforms?

No. Box sets like the CYMA 120-round mid-capacity magazines for M5 and MP5 models explicitly state that they do not fit HK platforms. Buying generic MP5 electric magazines without checking receiver compatibility leads to misfeeds, magazine well jamming, and wasted money on return shipping. Always verify model compatibility listings and part numbers to confirm whether a magazine is built for your specific receiver.

Can you shoot lead pellets or steel BBs in an Umarex MP5 airsoft rifle?

No. Umarex HK MP5 airsoft models are engineered exclusively for 6mm plastic BBs. Loading .177 or .22 caliber lead pellets, or steel BBs meant for an airgun or tactical air rifle, will jam the feeding nozzle and permanently score the inner barrel. Check the ammunition markings on your magazine and rifle receiver to ensure you only chamber smooth 6mm plastic rounds.

What is the most reliable way to reload MP5 airsoft magazines quickly?

Use a mechanical loader designed specifically for 6mm airsoft ammunition. The MetalTac L-012 speed loader holds 100 plastic 6mm BBs and works with standard-cap and mid-cap magazines across pistols, rifles, and shells. Depressing the plunger feeds rounds smoothly without bending feed lips or forcing BBs past the retention spring, keeping magazines ready for realistic training and plinking sessions.

How do you verify replacement magazine compatibility for Umarex gas platforms?

Match the exact model and part numbers listed in your gun manual against the replacement magazine. Umarex gas blowback systems require dedicated internal valves and exact feed geometry; for example, part number 2275005 is built specifically for the HK USP Compact GBB (models 2275013 and 2275004) and cannot be swapped into other platforms. If a product listing does not clearly identify your model number, check with the manufacturer before ordering to ensure proper seating and gas sealing.