The electronic pistol recoil haptics turned out fairly well. Not as powerful as pneumatic by far but feeling an impact for every shot with a pistol is nice. And its compatible with the mamut stock cups adding only 1/4" thickness to the offset of the cup locations. The battery pack is a trap on tripple LiIon with two magnetic USB charging lines that snake along the arms to the haptics. This way if they snag it just releases the magnet. The charge indicator on the battery is critical to ensure you don't overdischarge the lithium battery.
And Back to the pneumatic, I upgraded several aspects. First I removed the batter pack since liIons should not be mounted on a jack hammer for fear they may short and ignite. Instead I connect to a 12V supply via a magnetic coupled USB charging cable. The cable snakes along the pneumatic line both on a quick coupling connector and join the stock at the 2 point sling. The next upgrade will be the cylinder which should increase power and efficiency in the same volume.
