This might be one of the most pure fun rifles I own or have ever built to shoot. The combination of an SBR with a perfectly tuned gas system and binary trigger will dump rounds at an easy 400 to 600 rounds per minute. The foundation for this build is an Anderson lower receiver purchased on sale with White Oak Armament upper receiver and Spikes Tactical FN 11.5" cold hammer forged melonite 1:7 twist carbine length gas barrel which is the same 20,000 round rated barrel used on the M249 SAW. Like most of my builds this rifle has a FAB defence mag well funnel. The gas system is tuned with an MGI adjustible gas tube and the cyclic rate of fire is slowed with an MGI rate reduction buffer. The Franklin Armory binary trigger combined with tuned gas and buffer system is 100% reliable on single fire, double taps or full speed mag dumps which most mistake for select fire system. The sealed can is tack welded so that overall barrel length is over 16" and thus only requires one tax stamp. While loud with full power ammunition, its hearing safe enough to be able to run without ears ringing afterwards.

11.5" Mag Tactical SBR With Franklin Binary Trigger

   

   This rifle went together without a hitch but based on years of experience had a solid plan out of the gate. Normally I won't build an 11.5" barrel with carbine gas as dwell time of projectile in bore after passes port forces builder to overgas the gun. Knowing I was pinning a suppressor on this barrel which would increase the back pressure without worry of issues cropping up if can was removed. Will see majority of my swap barrels or Flash Can guns will have 12.5" to 14.7" barrels with approriate length gas to have plenty of dwell time of projectile in bore after passing port when run without a can. An overgassed gun will break extrators, bolts and even carriers. This as many of my AR 15's, AR 10's and others is topped with a Vortex Strikefire II (all my original Strike Fire's are still in service) which is one of my top choice closed tube 1x red dot optics.

MGI Adjustible Gas Tube

 

MGI Adjustible Gas Tube

 

  If look caefully can see the gas adjustment set screw staring out the first vent hole in top of standard AR 15 plastic forearms. When have a factory built rifle with front sight tower and I don't want to remove the front sight tower and rip apart the top end of the rifle just to swap over to adjustible gas the MGI tubes are the trick. Just remove the bolt, handguards, drift the gas tube roll pin out and with a little wiggling will have the original gas tube out, slide the MGI Adjustible gas tube into the upper receiver then slide into the gasblock till lined up and tap roll pin back in. Slap your handguards back on, put bolt carrier back in upper and follow directions to adjust gas on rifle. If running a suppressor or binary trigger adjustible gas is almost a necessity and with a short gas system and short barrel where have to force a lot of gas into the system for reliable function to tune it so have the least overgassed situation possible. I really like to use the MGI Rate Reduction Buffer with all short barrel binary builds and many mid length barrels. Often such rifles have as much as a 750 to 900 round per minute cyclic rate which is beating the rifle unnecessarily. Adjusting gas, proper selection of buffer springs (Tubb chrome silicone Flatwire almost always) and proper buffer weight. The MGI Rate Reduction Buffer looks like many hydraulic units but is a mechanical buffer that automatically reduces the cyclic rate of the gun from 100 to 300 rounds per minute. If it drops your 950 rpm rifle to 700 rpm and makes it more reliable and increases part life thats a win/win/win and how many shooters can accruately fire 900 rounds per minute from a semiauto rifle even with a binary trigger or bump fire. Read this independent review.

TACK WELDED SUPRESSOR

 

  Some people pin muzzle devices when trying to get a short barrel up to 16" legal rifle length but I usually prefer the four equidistant tack weld option. Can use a crush washer ans snug till just begins to compress then start a tack on top of the washer and let the puddle spread till just grabs the shoulder of barrel and device. It is nailed on solidly and legally, won't come loose and if ever decide to remove it just take a die grinder and cut through each weld into the crush washer till separates and once all are cut spin device off. Just a tad of touch up grinding and 99% of all people can never tell device or barrel were ever pinned and seen both destroyed at times by people trying to dig out a welded blind pin. Even if they get a pin out without damage the threads of barrel still have a portion where path for pin was drilled though them. I can and do pin as some devices are made ready to pin and sometimes dissimilar metals require it as I am not welding a titanium suppressor to steel barrel across an aluminum crush washer.

Franklin Binary Trigger

HOW TO INSTALL A FRANKLIN BINARY TRIGGER

  Rather than go though installation process of the Franklin Binary Trigger on every build we do please visit the trigger page in our build tips section for instructions on installing the system. Most people I see install these leave the red sticker off that warns people have a three position binary system in hand. I install the label on all my binary builds but being in the print business as well have made some in colors other than red but still bright enough to be easily noticed as someone could easily flip it to binary unknowingly and that round on release may happen when rifle is not pointed in safe direction.

Franklin Binary Trigger Factory Site

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