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Franklin Armory BFSIII M4 Binary Trigger Lower Receiver 5.56 NATO Black Hardcoat Anodize AR-15 / M4 Lower Receiver

Franklin Armory BFSIII M4 Binary Trigger lower receiver is built from forged 7075-T6 aluminum and finished in Type III hardcoat anodized black for durability. Designed for M4 / AR-15 pattern setups, it integrates the Franklin Armory Binary Firing System III for rapid follow-up shots and improved control with standard AR-style controls.

Key features

  • Forged 7075-T6 aluminum receiver with Type III hardcoat anodized black finish
  • Built-in Franklin Armory Binary Firing System III (BFSIII) for binary trigger operation
  • M4 / AR-15 pattern compatible for use with a 5.56 NATO upper
  • Specialized tension screw helps eliminate upper/lower play
  • M4-style carbine receiver extension compatible with a reinforced 6-position collapsible stock setup
  • Supports standard AR magazines with a 30-round configuration and restricted-state options (10/20 or 10/30)

Upgrade your M4 / AR-15 pattern build with a BFSIII binary-trigger lower receiver engineered for fit, function, and hard-use durability.

Franklin Armory BFSIII M4 Binary Trigger Lower Receiver: quick facts

What caliber is the Franklin Armory BFSIII M4 Binary Trigger Lower Receiver?
It is chambered in 5.56 NATO.
How many rounds does it hold?
30 rounds.
What kind of action does it use?
Double Action.
What sights and finish does it have?
finish: Black Hardcoat Anodize.
Is it new or used?
New, in the original packaging.
Can I buy it in South Carolina?
Yes. It ships to a licensed FFL dealer in South Carolina; you pick it up there after the background check. South Carolina buyers pick this up at a licensed dealer after a NICS check, with no permit and no waiting period; dealers sell rifles and shotguns from age 18.
Is it in stock?
Yes, at $421.19. Orders leave within 1-2 business days; shipping is free over $999.

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