Spatha-15 Enhanced Mil-Spec Lower

Our lowers are assembled by SOTAR-trained master armorers in North Carolina using components manufactured exclusively in the USA.

Below are some highlights of features of our Spatha-15EM lower:

• Aero Precision M4E1 Stripped Lower Receiver
  • The Aero M4E1 lower has the best combination of features, quality, and value for an AR-15.  It offers unlimited potential for a build.
• Everything Mil-Spec or Better
  • We build our lowers with true Mil-Spec or better components.  It is important to emphasize this because many claim to use Mil-Spec components, but use components made of inferior materials/quality.  We refuse to cut corners to save a buck.
• Buffer: Heavy (H1) Carbine Buffer
  • We use a heavy (H1) buffer in our EM and FC levels in the carbine series. The heavy buffer offers additional inertial resistance to the movement of the BCG out of battery, which increases the bolt lock time or “locked chamber dwell time” (which contributes to reliability and accuracy and reduces wear on your bolt).
• Buffer Spring: Mil-Spec Round Wire Buffer Spring
• Buttstock: Mil-Spec M4 Buttstock
• Grip: Mil-Spec A2 Grip
• Magazine Release Button: Mil-Spec Steel Magazine Release Button
• Receiver Extension: Schmid Tool 6-position, 4-hole, Dry Film Lube Carbine Receiver Extension
  • We went a little further than we had to for the receiver extension (buffer tube). We chose the Schmid Tool (because they are amazing) 7075-T6 tube and went with their 6-position series for the additional adjustability. We elected the 4 drain hole model, to allow drainage from the receiver extension if it ever gets submerged in the field. We went with a dry lubed version, because the buffed-in application of dry film lube improves the functionality and efficiency of the buffering system.
• Trigger: Schmid Tool GI Fire Control Group
  • We spent a little extra on the Schmid GI FCG. This trigger group is truly Mil-Spec (Schmid makes these for the Military) and it is masterfully executed. We should note that Mil-Spec is a lot better than what many companies put in their guns…as always, beware the “Mil-Spec” claims (or worse, a lack thereof).
• Safety Selector: Mil-Spec GI Safety Selector

Critical finishes and dimensions of individual components are inspected before they we accept them into inventory.  To learn more about our quality control gauging and inspection, visit our Quality Promise page.

Each upper receiver includes the following assembly and QC steps (full schedule of all 82 points of inspection for our builds can be found in our Quality Promise page):

• Receiver extension (buffer tube) threads lubricated with AeroShell grease.
• Receiver extension castle nut torqued to 40 ft. lbs.
• Receiver extension castle nut properly staked in two locations.
• Trigger sear, hammer sear notch, hammer hook, and disconnector honed, as necessary.
• Full lubrication with our own lubricant blend per our standard procedure.
• Full safety and function check per our standard procedure.
• Live fire test with M193 or M855.

The tables below detail what we put in the lower and what you are paying.

Spatha-15EM Lower Receiver (Black)

Spatha-15EM Lower Receiver (FDE)