WE ak74u GBB low FPS
 

Got the npas upgrade, have that installed and full i'm assuming open is shooting at about 200 fps, full or almost full closed is lightly propelling the bbs out of the barrel about 2 inches. My friend thinks it has something to do with the hopup or an improper seal somewhere around the npas upgrade.

have you tried adjusting the NPAS?

Yes, i'm not sure which increases the fps with it, open or closed, but it shoots 200ish fps or lightly propels the bb a couple inches out of the gun. And if i take the npas out, it is way too hot to play with.

Well crank it all the way clockwise, and then chrono it. If it's still dribbling bbs then crank it all the way counter-clockwise and chrono it again. If it still dribbles bbs, then your hop up is all the way on, your npas is not installed correctly, or you are not properly adjusting the npas. Inspect the nozzle for cracks.

thanks i'll try messing with the hopup, though i think its pretty well central. Problem with adjusting the npas is it rotates when using the key, so i either need to dismantle it all the way down to the kit or jam something in to hold it while i turn the key.

To adjust it, use a flat head or something else to hold the housing in place as you turn the key. Turn off your hop up to get an accurate FPS reading.

IIRC, you had to mod the nozzle so the NPAS works properly. I know I had to do it for a few guns

Npas is installed properly, but not getting any info on modding it for the ak74 anywhere.

Yep. A friend of mine got his AK PMC a while ago. Same problem. We're now trying to find a way to reduce the FPS with different floating valve springs, the problem is that too light a spring will make the gun inconsistent, this is because the relatively large amount of gas needed to cycle this gun will move flimsy/lighter springs around and make the closing of the valve insoncistent; so we're exploring different options to make it skirmishable. But for some reason, the OB NPAS does NOT work on the WE AK's, apparently it will work as if even in the closed (highest) setting, it was already too long to have any kind of considerable travel.


Fox.

It's the same mod done on the M4 and SCAR. Cut the two little tabs when the nozzle is apart, then cut a new one lower. Or cut an X like in the M14 nozzle. There's guides on this on RAtech's website.

Hmm. I didn't have to mod my npas for my scar....

Depends of your barrel lenght.

The NPAS valve is not a drop-in installation. The NPAS sits too far forward inside the nozzle which is why you are getting low fps readings. The nozzle requires modification so the the NPAS is in the proper position.

See this post:

http://www.airsoftcanada.com/showpos...&postcount=132

Thanks, this will be very helpful if i get the confidence to attempt this without wrecking it....tomorrow before my cqc game....lol

Thanks TPM001. You saved me a lot of trouble. With this MOD it now varies 340 to 400fps.