I shoot suppressed mostly and noticed the trigger pack gets quite dirty form doing so...
With the HBi springs installed, the disconnector would not allow the trigger to reset after the gun had been dirtied up. This would occur around 200 rounds of suppressed shooting. It felt like there was some drag in the reset and if I went to reset the trigger slow enough, it wouldn't reset without needing a forward push from behind the trigger shoe. Mind you, at this point, the contact points in the FCG had been lightly polished and lubed, yet this still occurred.
No, the trigger shoe roll pin isn't rubbing in the lower either...
My solution has been to go back to the factory disconnector spring with about 5 coils clipped off it(just guessing...I went with trial and error cutting 1/4 of a coil off at a time until it felt "right"). I also went and lightly filed down the hammer lip that the disconnector contacts and the under lip of the disconnnector. It was obvious when I disassembled the upper from the lower that the drag I was feeling was coming from the hammer and underlip of the disconnector. Filing them loosened the fit up leaving less "drag".
Filing the disconnector and hammer, polishing the snot out of all the contact surfaces in the FCG, customizing the factory disconnector spring, and using the HBi trigger spring has my trigger pack working finally. There is little to no drag now, little to no take up, and rest is defined and smooth. It even continues to work after shooting more than 200rnds suppressed!
So ya, HBi's disconnector spring helped cause me some headaches. I felt a few other HBi sprung scorpion triggers and they all seemed to have that drag. I am surprised more people have not had reset issues...In HBi's defense, it's not soley their springs fault. It has alot to do with the fit between the hammer and disconnector.