Sturm Ruger AC-556K .223REM 13″ bbl Factory 4-Position Select Fire Transferable Machine Gun


Sturm Ruger AC-556K .223REM 13″ bbl Factory 4-Position Select Fire Transferable Machine Gun

Listed By: CC Armory

Sept. 18, 2023, 2:31 p.m. - Unknown Section -
Listing Details

Transferable on a Form 3

Item Description

This Chester County Armory listing is for a Sturm Ruger AC-556K .223REM transferable factory machine. It is in it’s original factory “K” or “short” configuration, meaning it features the shorter 13″ original factory barrel, as well as it’s original iconic folding Ruger stock.

One of the few factory-made 4-position (safe, semi-auto, three round burst, and full-auto) machine guns made in the US, the Sturm Ruger AC-556 is still one of the more desired full-auto weapons available at a relatively reasonable NFA price tag left on the US transferable market. Designed and built like all of Ruger’s weapons (robust, with exceptional functionality), Bill Ruger’s entry into Class 3 weapons with the AC-556 was no different.  Designed in 1979 and based off the semi-auto Mini-14 that he (along with Jim Sullivan) created 6 years earlier as a scaled down version of the venerable M14 rifle, Ruger developed a workhouse of a gun, utilizing new manufacturing and engineering techniques to build a robust weapon that would be affordable to produce without sacrificing durability in any way. This occurred namely with the creation of a strong, investment cast receiver that was heat treated to withstand even the harshest of punishment.

This factory-made and registered machine gun is in excellent overall condition. The internal mechanics and the interior metalwork are excellent, with no dings, dents, cracks,  malformations, etc.. The internals on this weapon note only minor finish wear on the metal-to-metal contact points of the bolt and charging handle assembly. The bolt face is clean and crisp. The barrel remains clean, bright, and shiny, with excellent rifling. Cosmetically, the bluing of the receiver displays minor surface scratches and handling marks, and there are some minor scratches of note on the original rear sight assembly, however nothing more than cosmetic in nature. The wooden stock displays some minor indentations and light surface marks , but no chips, cracks, etc.. The folding stock lock-up remains tight and solid. The handguard and barrel are in excellent cosmetic condition, with only some minor storage wear noted on the front sight blade. Overall, this is an excellent investment model for the collector who also wishes to fire his machine guns.

According to the previous owner, Several years ago, this weapon was sent back to Ruger for their (no longer offered) factory full inspection and upgrade service for their Class 3 Weapons. This process allowed Ruger to fully inspect the machine gun and replace any necessary worn or broken parts (as they deemed necessary) to make sure the gun was within all factory specs. The previous owner stated that after receiving this model back from Ruger (having completed their full gunsmith inspection and upgrades), that this weapon has never been fired since. It was only safely stored and put away for investment purposes.

This factory transferable AC556K machine gun is currently on a Form 3 for easy eForm transfer. The current NFA paperwork lists “Sturm Ruger” as the manufacturer of this weapon and “AC-556K” as the model. The barrel length is also correctly listed as 13″ on the current Form 3.


For more information on this listing or to view our other NFA and investment grade firearms, please visit our website at, or contact us via the information listed below.


Chester County Armory

West Chester, PA


phone: 610-235-6155

Extra Details:

  • State Tax: $6.00
  • Publish date: Sept. 18, 2023, 2:31 p.m.
  • Expiring Date: Sept. 25, 2023, 2:31 p.m.

Seller Info

  • Shipping: Seller Will Ship!
  • Location: Pennsylvania
  • Listing ID: #15252