We covered the Vadum electronic .22 LR several months ago with a comprehensive review on TFB (very solid review by Tom R). Since then, the Vadum team has been working away at the design, and had it not only on display at Bullpup 2016 but also available for live fire down at the demo ranges.
So what makes the Vadum electronic? The only electronic part of this firearm is the trigger linkage to the hammer. The trigger is attached to a bar that presses down on an electronic apparatus which then allows the hammer to fall per single trigger press. This apparatus is charged via a 9 Volt battery which is slid in through the right side of the frame. An Off/On switch can turn the apparatus off and on, and is mounted on the left side of the frame, just ahead of the trigger. If the battery runs out, there is no secondary manual hammer system should the electronic fail. One of the biggest drawbacks of bullpups from a civilian perspective are the long trigger linkages that cause excessive trigger pull. With electronics, the eBP-22 is able to get the pull down to mere ounces instead of pounds.
The rifle has much in common with the Ruger 10/22 platform, sharing the barrel and magazines. The bolt is a factory Ruger bolt, modified to include a rear radius (smoother charging, better cycling with standard velocity and subsonic), as well as a firing pin anti-rise crosspin. It will accept standard unmodified Ruger bolts as well.. The frame is very nicely designed, being compact, with a telescoping stock that slides right into the overall frame. The company has incorporated common features such as picatinny rails, an AR style pistol grip, and a threaded barrel for suppressors.