Hi capa Standard Division build problems- Weak blow back, not cycling completely
 

So i recently started to build a standard vision Hi capa from the the ground up using Airsoft Masterpiece complete SAI slide kit and frame. However i'm running into weak blowback issues. The gun only cycles half way and doesn't allow the hammer to engage all the way.

Its definitely not the upper assembly since i tried it on another frame and it works properly(there isn't much there that could affect it honestly other than the nozzle and blow housing assembly and piston). I've checked the inner parts and the sear, valve knocker, hammer, valve reset, and disconnector seem to all work properly (as in it does engage when i manually pull it back and releases, as well as resets the trigger). It just doesn't cycle all the way when its actually being fired.

Any ideas what could be the issue?

Currently using a guarder 150% recoil and hammer spring with shock buffers. Frame, valve knocker and sear and Airsoft masterpiece and the hammer is UAC with a nova hammer strut.

Any help would be much appreciated. Thanks!

Does a slide from another hi capa function on the lower of your gun? Perhaps the gas is getting cut off too early by the blow back unit.

Is it venting gas when it stops half cycle?

Did you try with a no gas in mag ,no slide on to see how the valve striker connects with the release valve on the mag.

SOmetimes when you tighten the grip to the frame you can put a slight forward or backward tilt as to how the mag meets the striker through the grip magwell alignment

SOmetimes you can overtighten the grip screws as well as the piston housing screw to the
slide and cause finicky issues

Did you upgrade the mag feed lips or gas route buckings ? Those can cause certain issues as well

Nope it is not venting gas when it half cycles. The valve is hitting the valve properly. I tried another slide is it functions much better. Mags are completely stock except for the upgraded nineball rubber.

I tried a stock blowback unit and it does the same thing. I tried the slide on another Airsoft masterpiece frame and it works much better

Update I messed with the leaf spring a bit and now it cycles fully (but weak) more than before but sometimes it still cycles half way

update: I put in a factory hammer spring and noticed a huge difference in cycling but still wasn't 100%. I cut it down by about 2 coils and now it seems to function really well.

But this still seems like a temporary fix to me, i shouldn't have to cut down a factory spring for the gun to work properly.

Has anyone else encountered this issue before?