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Matrix CNC Machined Hybrid Hopup Chamber for WA / G&P WOC Airsoft M4 GBB Rifle

ID: 36754 (HU-MTX-WAM4Hyb)
5.0 stars, based on 1 reviews
Matrix CNC Machined Hybrid Hopup Chamber for WA / G&P WOC Airsoft M4 GBB Rifle
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This item is currently Out of Stock Usually restocked within 1-3 weeks.
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  • High Quality CNC Machining
  • Tough Black Anodized Coating
  • Hybrid Design allows the use of AEG Inner Barrels (GBB Inner barrels not compatible with this design)

  • Application: Allows the use of AEG Inner Barrels in WA M4 GBBs (GBB barrels are NOT compatible with this hopup unit)
    Compatibility: For use with Western Arms and G&P WOC Airsoft M4 GBB Rifles
    * Will not work well with Madbull bucking and other super thick bucking.

    Disclaimer: Please use discretion when installing custom parts as fit and compatibility may vary. Some modification may be required. Professional installation recommended.

    California residents click here for Proposition 65 warning

    1 Customer Review

    (Write a review)

    by Eric C. on 06/28/2017
    "This was an excellent upgrade over the stock hop adjust system in my King Arms WA-system M4. The degree of hop is adjusted via a 2mm allen wrench inserted just below the chamber with the receivers hinged apart. With a free-float RIS attached, the stock King Arms hop adjust was inaccessible.

    So far, however, it has eaten through a Prometheus purple bucking (over the course of two games) and an Angel Custom V-teeth orange bucking (over the course of two shots). And it may or may not have contributed to the destruction of the stock plastic loading nozzle. But I have high hopes for the Madbull 60 degree Shark red bucking []. It required slight trimming on the forward end and a little bit of massaging to get it to fit, but it seems to fit snugly without protruding too far into the path of the new aluminum loading nozzle. The chamber can't take all the blame for being hungry. It's really a problem with how all of the pieces fit together - barrel, bucking, hop chamber, and feeding nozzle. So each unique build will have its own quirks. Best to have spare buckings on hand just in case.

    Because I contradict the description, which says that Madbull buckings may not fit, here are the other mechanical parts of my build: King Arms receiver, barrel, and outer barrel, RA-Tech steel bolt carrier, and RA-Tech aluminum loading nozzle, bolt, locking plate, and NPAS. Again, it did require some trimming and massaging, but there are no signs yet of shredding which makes it a better candidate already than the other two I've tried.

    The solid pin that holds the arm in place fits very tightly. You might want to bring the chamber to the hardware store to find one that fits -just- snug if you want to be able to remove the arm. Coaxing the spacer into place is a delicate and frustrating task if you can't remove the arm. Also, the tiny spring that sits between the hex nut and the forward wedge likes to fall out if you're not mindful when dis/assembling the barrel. I ended up replacing mine with a spare rubber hop spacer.
    In short:

    Easier to adjust hop
    Compatible with AEG barrels and spacers

    Small, easy-to-lose parts
    Finicky about which buckings it likes
    Difficult to get spacers in place

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    This item is currently Out of Stock. Most out of stock items are restocked within 1-3 weeks. Some items may take longer. Please add this item to your wishlist to keep posted on its availability.