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BKF M4 MOD-1 Standard Power 4.5lb Two Stage Combat Control Magpul SL Lower Build Kit (Nickel Boron)

Original price was: $373.54.Current price is: $289.49.

33 in stock



New for 2019 is our BKF M4 MOD-1 Product line that is part of our new Premium Series. The Premium Series will offer a vast number of BKF components that have been made with the AR builder in mind. Not only does the Premium Series offer extremely high quality products, but it also offers very competitive pricing. These are not any old AR15 mil spec components . They feature BKF signature machined pocketing and enhanced aesthetics. All of the detail is machined to give this Buffer Assembly a refined look. This lower Build Kit is the perfect starting place for any high quality build.

This is standard in all rifle length 5.56mm/223 wylde weapon systems ranging from 18″ to 20″. This is also standard in all of our 300 Blackout weapon systems. 

BKF AR15 Lightweight 8 Position Anti-Tilt Carbine Length Buffer Tube Features:

  • Billet machined from 6061-T651 aluminum for tighter concentricity than a forging or impact extrusion to reduce potential for bolt carrier binding.
  • Mil Spec extension diameter of 1.148, and thread diameter of 1.185
  • Mil Spec Carbine length
  • Extended carrier support flange that supports the carrier for better anti-tilt performance.
  • Self aligns with the buffer detent.
  • Fluted for a more aesthetic look
  • 3 Drain holes at 6 O’clock Rear holes
  • SAPA Forging / ASTM Certified
  • Proudly made in the USA!!!

Lower Build Kit Includes:

  • BKF M4 MOD-0 Standard Power Carbine Buffer Tube Assembly (3oz buffer with sprinco white)
  • BKF AR15 Enhanced M4 MOD-1 Combat Control 4.5lb Two Stage Lower Parts Kit (LPK) (Nitride components, BKF AR15 TF Two Stage Nickel Boron Complete Fire Control Group, Billet Slotted trigger guard, Combat Control Kit and moe grip)
  • Magpul SL Carbine Stock

Sprinco WHITE AR15 Standard “Regular” Power Spring:

Equivalent spring power of a “fresh” AR15/M4 carbine action spring, this spring is for users who do not want to dabble with improving performance with extra power springs, but do not want to frequently replace their action springs as well.

Standard AR15/M4 buffer springs (aka “action springs”) are wear items which must be replaced regularly in order for AR-15s to operate reliably, with conservative replacement taking place every 5000 rounds. Sprinco action springs in comparison, are over engineered and will last over 50,000 cycles.

Sprinco Chrome Silicon buffer springs are heat treated, stress relieved, and dual-stage shot peened in separate post winding treatments.  Sprinco also treats each spring with a proprietary, deep-penetrating, re-micronized (to .3 Micron particle size), inhibited, Molybdenum-Disulfide (MoS2) formulation to eliminate 90% of all mechanical wear on the spring:  this is why Sprinco springs do not produce the spring sound during shooting which is common with standard action springs.


Additional information

Weight .5 lbs
Dimensions 10 × 2 × 2 in


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