The Fostech Echo goes all the way up to three. (Shown here at two.)
Fostech Outdoors, makers of the Origin-12 series of semi-automatic shotguns and Bumpski
bump-fire stock for AKs, recently received ATF approval to manufacture a new drop-in rapid-fire trigger designed for AR-15-pattern rifles. It’s a trigger that fires on the initial pull and then again on the reset!
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