SOTM4MOD1 A5 Forged Complete Lower Receiver
SOTM4 forged · Schmid two-stage DLC · Geissele Posi-Snap and Maritime · SOT A5 nine-position tube · A5H2 · B5 Systems Bravo
The forged lower, complete.
CONFIGURATION SHOWN: SOTM4MOD1 A5 Forged Complete Lower Receiver — FDE: FDE B5 Systems Bravo stock and Type 23 grip, receiver black anodized. Upper, bolt carrier group, charging handle and magazine not included.
The lower the forged rifles are built on, sold complete.
The SOTM4MOD1 A5 forged lower from the SOTM4A5 Forged Series: Schmid Inside Elite two-stage DLC trigger, Geissele Ambi Posi-Snap selector and Maritime bolt catch, button magazine release, SOT A5 nine-position buffer tube with an A5H2 buffer and Forward Controls Design CN5F extended castle nut, B5 Systems Bravo stock and Type 23 grip in FDE or black. Fits any Mil-Spec AR-15 upper.
The lower the forged rifles are built on
This is the SOTM4MOD1 A5 forged lower from the SOTM4A5 Forged Series rifles, sold complete: the same trigger, controls and A5 recoil system, ready for any Mil-Spec AR-15 upper.
What forged buys: strength and universal fit
Forging presses the 7075 aluminum into shape instead of cutting it from a solid block, so the grain of the metal follows the shape of the receiver. That makes a forged lower stronger than a billet one, and tougher against impact and hard use. It is held to Mil-Spec dimensions, so it pairs with any Mil-Spec AR-15 upper.
A two-stage trigger as standard
The Schmid Inside Elite two-stage in DLC: 3.5 lb total, 2.0 lb to the wall and 1.5 lb to break. The Geissele G2S® or the LaRue Tactical MBT-2S can be installed instead, for $100.00 more. Second of Ten does not stone, polish or modify sear engagement surfaces.
Numbered stock positions
The SOT A5 buffer tube has nine positions, with numeric index marks 1 through 8 laser engraved on it. The B5 Systems Bravo stock has a window over the tube, so you can read the setting at a glance and return to it.
A5 recoil system, staked and locked
A5H2 buffer and rifle-length spring in the A5 tube, a Forward Controls Design CN5F extended castle nut staked into the B5 Systems QD end plate, and Vibra-TITE VC-3 on the threads.
Controls
Geissele Ambi Posi-Snap selector, Geissele Maritime bolt catch (left side; this version has no ambidextrous bolt release), button magazine release, nitride takedown and pivot pins.
| SKU | Option | Price |
|---|---|---|
| LWR-SOTM4MOD1A5-F-BLKFDE | FDE Furniture | Price to be confirmed |
| LWR-SOTM4MOD1A5-F-BLK | Black | Price to be confirmed |
| Option | Choice | Price |
|---|---|---|
| Trigger | Schmid Inside Elite 2-Stage, DLC, curved bow (standard) | Included |
| Geissele Automatics G2S® two-stage, installed | +$100.00 | |
| LaRue Tactical MBT-2S two-stage, curved or straight bow, installed | +$100.00 |
Where this lower can ship
Not available in California, Connecticut, Delaware, Illinois, Maryland, Massachusetts, New Jersey, New York, Rhode Island, Washington or Washington, D.C. A lower receiver is a serialized firearm and ships to your FFL dealer only. Laws change: please confirm with your local FFL before ordering.
Photography © Second of Ten LLC. MONOBLOC® and HMB™ are marks of HM Defense, LLC, used under license. Bombproof by Design™ is a mark of Second of Ten LLC. Cerakote® is a mark of NIC Industries; G2S®, Posi-Snap and Maritime of Geissele Automatics; MBT-2S of LaRue Tactical; Inside Elite of Schmid Inside; WARHAMMER of Breek Arms; CN5F of Forward Controls Design; Bravo and Type 23 of B5 Systems; L5AWM® of Lancer Systems; PMAG®, GEN M3™ and MBUS® of Magpul Industries; MuzzLok® of Faxon Firearms; Vibra-TITE of ND Industries; M-LOK® of Magpul Industries. Marks are the property of their owners; their appearance indicates that Second of Ten incorporates the component, not sponsorship, affiliation or endorsement. Prices in USD, subject to change; the product page shows the current price and availability. Second of Ten LLC · Stuart, Florida · FFL 07 / SOT Class 02.
| Version | Date | Change |
|---|---|---|
| 1.2 | 2 NOV 2026 | Forged vs billet corrected: forged receivers are the stronger (grain follows the part); billet holds tighter tolerances. |
| 1.1 | 2 NOV 2026 | Photographs levelled on the receiver and buffer tube axis. |
| 1.0 | 2 NOV 2026 | First issue |