Acquisition—Aero Precision M4E1 Low Profile Stripped Lower

I actually picked this one up about a year ago and then promptly forgot about it, only recently re-discovering it in the process of tidying up the safe.

Most readers will know Aero Precision M4E1 lowers are full-featured AR receivers that are engineered to strike a balance between advanced features (versus run-of-the-Mil forged components) and a reasonable price point.

This one is the “low profile” version, which has nothing to do with any dimensional spec but rather flies under the radar because it carries no overt branding on the starboard side, eschewing the traditional, fairly conspicuous Aero Precision logo in favor of a small, unobtrusive one on the port (serialized) side.

The M4E1 family of stripped lowers integrates the sorts of niceties you’d find on a more expensive billet lower while giving you the relative cost savings of a forged piece. It is a forged 7075 aluminum unit with a loosely Mil appearance, but not explicitly Mil-spec because of the added features.

These features include an integrated flared trigger guard, a modestly flared magwell, and a threaded pin for the bolt release in lieu of a traditional tap-in roll pin. The rear takedown detent recess is also threaded to ease installation of the detent and spring with a 4-40 set screw. The safety selector port is milled and marked to accept short-throw selectors.

The M4E1 also includes a nylon-tipped upper-tensioning screw installed at the rear that you can use to stabilize the upper receiver against the lower, useful for eliminating any slop or wobble when mixing and matching receiver sets from different manufacturers.

Since the “low profile” unit was released, Aero has also released an M4E1 Pro version that mimics the low profile aesthetic and includes ambidextrous controls for the bolt and magazine releases pre-installed, along with all the other features that already make an M4E1 unit great.

Various finishes are available, including raw aluminum and select colors of anodize or Cerakote. This one is the standard black anodized version.

Our plan here is to build the lower out with an Aero enhanced carbine buffer tube/carbine buffer setup and CMMG Zeroed LPK and controls. The completed lower will then mate with a duty-grade upper assembly at some point in the near future.

Stay tuned.

Aero Precision
M4E1 Low Profile Stripped Lower Receiver
MSRP: $155
URL: aeroprecision.com