The Magnificent Franklin Armory Binary Firing System

The Double Tap Made Easy

1. Relating to, composed of, or involving two things.

Anything worth shooting is worth shooting twice. The man who first taught me that was the hardest soldier I have ever known. After three combat tours in Vietnam, that guy knew how to run a gun. His wisdom was indeed timeless.

At first brush, the Franklin Armory Binary Firing System (BFS) seems like some gimmicky range toy … only it’s not. This top-quality drop-in firearms accessory is designed by serious folks to make you a seriously better shooter. In addition to being just great fun, the Franklin Armory BFS will cut your split times and can make you more effective on the range.

The Franklin Armory Binary Firing System is a drop-in conversion unit designed for a wide variety of host weapons
that allows the gun to fire once when the trigger is pulled and again as it is released.


The National Firearms Act defines a machinegun as: Any weapon which shoots, is designed to shoot, or can be readily restored to shoot, automatically more than one shot without manual reloading, by a single function of the trigger.

The mad geniuses at Franklin Armory have contrived a mechanism that allows you to fire your favorite sporting weapon once when you pull the trigger and again when you release it. In so doing, the gun still shoots one time for each single function of the trigger. That keeps the feds happy. However, a full trigger cycle produces a reliable double tap that minimizes disturbances to your sight picture and makes for faster follow-up shots.

Franklin Armory offers fifteen different variations for a wide variety of common weapons, including the AR15, AKM, GLOCK, Stribog, HK clones, Ruger 10/22, CZ Scorpion, PC Charger, and more. Each design is unique, but they all share some common DNA. Their conversion units drop in without gunsmithing and offer three different selector options. Safe and traditional semiauto are fairly straightforward. The Binary position, however, is where the real magic can be found.

When set for Binary fire, you get one round on pull of the trigger and one round on release. Before I met one of these things, I thought it was just a nifty way to waste ammo. After a little range time, I found the rig to be surprisingly practical.

The Franklin Armory Binary Firing System was a drop-in fit for my tricked-out Century Arms AP5-P/MP5K PDW clone.

Roller-Locked Hosts

We reviewed the HK Binary trigger module. This self-contained unit replaces the fire control box on your roller-locked HK clones. There is no sear trip, so the plug-and-play Franklin Armory Binary Firing System works fine with a factory semiauto bolt carrier.

Where previously, these German-made, roller-locked guns were prohibitively expensive, nowadays, lots of folks make them. The quality of the Turkish examples I have sampled from Century Arms rivals that of the German factory weapons. A single Franklin Armory BFS unit will service the 9mm MP5, 5.56mm HK93, 7.62x51mm HK91, or any of their analogs regardless of pedigree. The HK BFS includes a stronger hammer spring to be used with the 5.56mm and 7.62mm examples. The Franklin Armory Binary Firing System will take these conventional sporting weapons to the next level.

My Century AP5-P is registered as a short-barreled rifle with all the bells and whistles. Install the Franklin Armory BFS, and you have a compact and controllable pocket carbine that is fun and effective in comparable measure. Exercising it will make you feel like a spy.

Besides being an epically fun range toy, the Franklin Armory Binary Firing System also has practical applications,
particularly for competition.

Franklin Armory offers its Binary Firing System for a wide variety of popular guns,
including roller-locked HK clones and the GLOCK 17 pistol.

Trigger Time

The manual of arms is unchanged from that of the conventional weapon. You cycle the trigger just as you might with a lesser gun. However, the Franklin Armory Binary Firing System lets you hit the target twice instead of just once.

The obvious question is, what happens if the range goes cold before you release the trigger and fire that next round? All of the Franklin Armory Binary triggers are designed in such a way that you can move the selector to the semiauto position and automatically disengage the Binary function. In so doing, the gun returns to its base traditional semiautomatic state, even if the trigger has already been staged.

Some seasoned shooters will invariably turn their noses up at the very thought of a rapid-fire Binary mag dump. I’d be willing to bet those guys are no fun at parties and don’t have many friends. Check out YouTube. That’s the next best thing to rock and roll.

The Franklin Armory Binary Firing System in my MP5K PDW clone is both surprisingly effective and a hoot to shoot. Fun aside, the use of a BFS in real-world defensive situations is compelling. A Binary trigger makes the all-important double tap into center mass that is taught by so many instructors quite easy to achieve. However, just like with any other defensive use of a firearm, ample training with your Binary trigger is always the best approach.

Running the Franklin Armory Binary Firing System well takes a little practice. However, I printed these two-shot groups
at typical CQB ranges off of a simple rest. Wow!


The end result is reliable, inspired and cool. With a little range time, it is a simple thing to fire controlled and effective hammer pairs by judicious manipulation of the Franklin Armory BFS. Throughout it all, the gun remains both soft-shooting and controllable. The Franklin Armory Binary Firing System makes good guns great.