New Frontier Armory

C-4 Billet Lower

(3 Reviews)
Category: Stripped Lower Receivers Lower Receivers
$69.99 $119.00
You save $49.01
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C-4 Stripped AR-15 Billet Lower Receiver

Manufacturer:New Frontier Armory

Model: C-4

Type: AR-15 Stripped Lower Receiver

Caliber:Multi (will accept any upper and/or caliber designed for the AR-15 platform)

Magazine:Accepts any standard MIL-SPEC AR-15 magazine

Finish: Anodized or RAW (media-blast only)

Weight:10.4 oz

Other Specifications and Features of the C-4 Stripped AR-15 Lower Receiver:

  • Machined from 7075-T6 aircraft grade billet aluminum
  • Matte black hard-coat anodized per Mil 8625 Type 3 Class 2 or RAW (media-blast) finish ready for Cerekote, Duracoat, and other custom finishes
  • Precision broached magazine well with beveled feed lips
  • Machined and engraved to be compatible with 45 and 60 degree short throw fire control selectors such as the BAD_ASS ST 45 Lever
  • Caliber marking of "Multi" so it can be used with many different caliber uppers
  • Compatible with all standard AR-15 components and magazines and most aftermarket parts
  • Take down pin spring and detent hole is threaded for a 6-32 set screw for easy capturing (hardware included)
  • Upper tension screw behind grip screw (threaded hole with hardware included) to adjust any “slop” out of vertical fit between upper and lower
  • Ambidextrous trigger finger rests with grooves (above and below mag release / mag catch)
  • Compatible with Norgon and other aftermarket ambidextrous mag releases
  • Threaded bolt catch pin (Threaded hole and hardware)
  • Integrated large opening "winter" trigger guard
  • Manufactured to MILSPEC on state of the art CNC equipment for consistent quality parts and exacting tolerances
  • Save money by building your own AR-15 rifle from the ground up exactly the way you want it configured

The New Frontier Armory C-4 Stripped Billet AR-15 lower receiver is proudlyMADE IN THE USAby hard working American men and women.


This is a serialized item considered to be a firearm by BATFE. This item must be shipped to a Federal Firearm License (FFL) holder. All BATFE, GCA & NFA rules apply! This item must be shipped to a Federal Firearm License (FFL) holder. You will be prompted during checkout to pick an FFL to ship to in your area using our FFL Locate tool.YOU will be responsible for checking with your local FFL to ensure this weapon is legal in the state that you reside and that they will accept this weapon on your behalf and transfer it to you.New Frontier Armory, LLC will NOT be responsible for any shipping or admin charges incurred by packages not being accepted by the FFL you choose during checkout.

Reviews (3)

C4 lower

Written by Danny Lee Cornelius on 24th May 2023

This is an awesome product. I will not be buying plain mil-spec lowers anymore.....i think NFA does a great job on quality and service. Thank you and I will be ordering more

Very well made lower

Written by Thomas Beckham on 6th Apr 2023

I’ve used New Frontier lowers before and have been very satisfied with them. I was particularly pleased to find the Allen screw keeper for the takedown spring and detent was provided although I’d already purchased a supply of them.

Written by on 21st Oct 2014

As a manufacturer of firearms, this is the best looking and most "user friendly" lower I've ever had the pleasure to work with. With the lower to upper tension screw, you can throw away those silly "accu-wedge" shims. The takedown pin spring set screw makes the assembly of the receiver extension a breeze. The threaded bolt catch pin removes the extra work and care required to set the old style roll pins without damaging the finish on the lower. Anti-walk trigger pins fit more exactly to the somewhat wider width of the lower's exterior dimensions. The select fire marking is great for those fire control drop-ins such as the Tac-con 3MR. New Frontier is a great company with industry leading innovations such as the side charge billet upper.

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