The term Mechanical Trigger refers to the type of trigger design on over and under shotguns that makes it possible to pull the trigger and release a hammer with each pull of the trigger, regardless of whether the first shot fires. Most over and unders have inertia trigger systems. The difference between mechanical and inertia systems is detailed here.
Two Browning over and under shotguns currently have mechanical triggers. They are the Citori 725 and the Cynergy. These two high-performance Browning shotguns have been fitted with these exclusive mechanical trigger designs to meet the needs of performance shotgunners who desire second shot capability regardless of whether the first pull of the trigger fires the shell or not. Reliable mechanical triggers are esteemed n in the firearms industry. Mechanical trigger systems are often desired by expert level clay target shooters who want an elevated level of speed and control. Some systems over the years sacrificed trigger pull and feel to achieve this. Browning's trigger system designs overcome this limitation.
Cynergy. The Cynergy features the innovative Reverse Striker ignition system; a striker-based, mechanical trigger that offers the benefits of a crisp feel, reduced locktime and less overtravel than other over and under shotguns. Because inertia is not needed for the hammers to set, the design eliminates the possibility of the second barrel not firing.
Citori 725. The exclusive new Fire Lite Mechanical Trigger is a big part of the Citori 725's performance package. The innovative design features reduced take up, a crisp break and shorter overtravel. Inertia is not needed to reset hammer for the second barrel.
This diagram shows the mechanical trigger system found on the Browning 725 over and under.
The excerpt below on trigger function is taken from the Cynergy owner's manual. Many owner's manuals are available for download and are found under the Support tab along the top menu of most pages on browning.com
"Unlike other over and under shotguns, the Cynergy features the Reverse Striker Trigger System. The Reverse Striker is a mechanical
trigger system rather than a traditional recoil-actuated trigger system. With the Reverse Striker, after one barrel has been fired the trigger shifts itself into position to fire the second barrel when the trigger is pulled for the second shot. It will not fire both barrels simultaneously. Only one barrel will be fired with each pull of the trigger."