How do i keep the hopup nub from falling off the arm

[Reeko]

I bought a new SCS nub for my hopup, and i put it on the adjustment arm, but it doesnt really stay there, even when its inside the hopup, it doesnt adjust up and down with the rest of the arm.

[Payback]

try a little dab of AEG greese on the nub.

[Reeko]

alright got it, my gun was shooting 2 bb's at once too, but i think it was the mags. I changed to a hicap and it worked fine. I wonder if my midcaps are faulty or something

[Payback]

Make sure that your bucking is seated into the back of the hopup fully. Your mids may just have a higher spring and able to push the extra bb in where the high cap doesn't. Double feed can happen if the bucking is too far forward, among other things.