Description
Ra Tech NPAS Kit for MP7 & System 7 GBB
This RA-Tech NPAS kit is made for MP7 gas blowback SMGs and other replicas using System 7 technology. NPAS stands for Negative Pressure Adjustment System: an adjustable valve in the nozzle assembly that lets you tune how much gas goes into firing each BB.
RA-Tech is a well-known maker of GBB upgrade parts. A Hong Kong retailer lists an RA-Tech NPAS valve for KSC and KWA MP7 SMGs, other System 7 GBBs and the KJ Works M4 GBB, describing it as giving more reliable shot-to-shot power and letting you lower power well below, or raise it slightly above, factory settings.
Why fit an NPAS
Power limits vary from site to site, especially between CQB and outdoor venues. An NPAS lets you set your MP7 to suit without changing springs or switching gas, and it helps keep each shot more even. It is one of the most useful upgrades for players who move between sites.
Setting it up
Adjust in small steps and test each change on a chronograph with the BB weight and gas you play with. Note the final setting, and recheck if you change gas, BB weight or play in very different temperatures.
Fitting
Unload the gun and remove the magazine. Fitting involves removing the bolt and working on the loading nozzle. Take your time, keep small parts safe and, if you are unsure, have it fitted by a technician.
Key features
- RA-Tech NPAS for MP7 and System 7 GBBs
- Adjustable power, up or down
- More consistent shot-to-shot power
- Approx. 32mm valve (per retailer listing)
- Tune your gun for each site
- Popular GBB upgrade
Compatibility
Listed for MP7 and System 7 GBBs; a retailer lists the RA-Tech valve for KSC/KWA MP7, other System 7 GBBs and the KJ Works M4 GBB. Other MP7 GBBs, such as Tokyo Marui’s, may need a different NPAS, so check your model before ordering.
Care and maintenance
Keep the nozzle and bolt clean and lubricate seals and O-rings with silicone oil. Store magazines with a little gas to keep seals seated, and recheck power regularly on a chronograph.
Who is it for?
It is for KSC, KWA and other System 7 MP7 owners who want to tune power for different sites and get more consistent shots.
Please note: Always chronograph after fitting and adjusting. Technician fitting recommended. Always wear eye protection.
