WE Airsoft P90 Metal Upper Receiver Adapter

thingiverse

The WE P90 is a fun airsoft gun. One disappointment for me was the light plastic tri-rail upper. This adapter lets you run a metal AEG spec upper (in this case a Classic Army upper which happens to be on sale right now for $35 US https://www.evike.com/products/81084/) which brings the rifle to a more realistic weight and also allows you to run the proprietary P90 sights instead of the tri-rail setup. Some minor modifications are necessary to the upper but overall it's a very good fit - almost drop in. No modifications are required to any of the WE parts unless you want to avoid having to increase the length of the charging handle slots which pretty much requires the use of a dremel and a steady hand. The metal is heavy but very soft so I don't think any of these mods are too challenging if you take your time with a dremel and hand file. If you want to avoid messing with the slot you can just file off the tabs on the inside of the plastic charging handles. The spacer is included because the hop chamber requires a relatively precise position to work with the magazine and internal gas tank valve. For me this all worked with the spacer at the nominal length, but if your printer and tolerances vary you can adjust this spacer to control the fore/aft position of the hop chamber.