CLOSEOUT – Lead & Steel All-Rounder Carbine (ARC) 12.5″ Upper Receiver Group, Anodized Black

5.00 out of 5
(1 customer review)


In stock

In stock


Lead & Steel All-Rounder Carbine (ARC) 12.5″ Upper Receiver Group, Complete – Anodized Black

Introducing the Lead & Steel All-Rounder Carbine (ARC) Upper Receiver!

Weighing in at <2.8 lbs., the ARC offers one of the most durable upper receiver assemblies in the industry. This is not a simple commercial offering; these uppers are made for high-volume shooters who expect consistency & reliability with every shot.

Barrel Features:

The patented 1:8 twist 5.56x45mm 12.5″ Midlength Chrome Lined HM Defense MonoBloc barrel provides many advantages over the traditional gas block system. With the gas block integrally machined as part of the barrel, common AR-15 gas system headaches are practically eliminated. This includes:

  • Gas block leaks.
  • Gas block misalignment.
  • Gas block installation errors utilizing set screws, loctite, pinning, etc.
  • Varied thermal expansion coefficients.
  • Impingement of M-LOK accessories against the gas block at the 6 o’clock position of the rail.
  • Permanently affixing a handguard to a pinned & welded barrel – the barrel nut freely glides over the block, giving you the ability to swap rails with a P&W muzzle device.

The MonoBloc barrel solves nearly every gas system issue in the industry & offers absolute peace of mind. Paired with Lead & Steel’s chrome lining, match crown, and lightweight profiling, the MonoBloc barrel offers exceptional barrel life & corrosion resistance.

Buffer disclaimer: We recommend the use of a standard carbine spring & buffer if shooting unsuppressed.

This complete upper includes:

The ARC sets a new benchmark for duty grade rifles.

Each complete rifle is gauged & test fired for optimum reliability in a variety of environments.

Our patent-pending free-float rail utilizes a unique wedge-locking interface that does not stress the handguard like traditional clamp-style free-float rails.

The optional muzzle device is internally & externally threaded. Internal serrations disrupt flash expansion & external threads are implemented for mounting a QD lightweight concussion-reduction device.

Finally, our buffer tubes, receivers & rails are Type-III, hard-coat anodized in various colors for your preference.

If you need a “one & done” AR-15, look no further than the ARC!

Short enough for close engagements, with ample velocity stemming from the 12.5″ suppressor-ready MonoBloc barrel. Find out why the ARC belongs in your stable!

Read more about HM Defense’s MonoBloc technology, from the Lead & Steelopedia in our Knowledge Center, here.


Aluminum anodizing might as well be wizardry. Color options will always have some variance in shade & hue. Please understand that Lead & Steel makes no guarantees on the exact shade/hue of brown or black that you purchase.

These uppers are manufactured as duty grade equipment. You may find cosmetic evidence of testing & QC upon delivery. This is completely normal & allows us to only deliver upper receivers that pass our strict quality control.

1 review for CLOSEOUT – Lead & Steel All-Rounder Carbine (ARC) 12.5″ Upper Receiver Group, Anodized Black

  1. 5 out of 5

    Ethan V. (verified owner)

    Bang for you buck? Can’t beat it. Was going to build with the hm but this was more cost effective. Going to try to run it with a viltor buffer system to see how soft and reliable I can get it

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