The Midwest Alpha Series M4 Beam is a modular tactical stock accessory designed for shooters who need a versatile, durable solution for AR-platform rifles. Midwest Industries engineered this beam stock to deliver the strength of steel construction with the flexibility to adapt to your setup—whether you're building a precision rifle, a home-defense AR, or a tactical carbine. Available in two configurations, the side-folding model and the fixed Picatinny-rail attachment version, the Alpha Series M4 Beam lets you choose the platform that fits your mission.
The side-folder version is built around a heavy-duty 4140 steel folding mechanism with a full-length locking lug for maximum strength and a positive lock in both extended and folded positions. The steel clamp features broad surface engagement for rock-solid attachment, and the curved beam top reduces wobble that can occur with skeletonized designs. You can configure it for right or left folding, and its modular design means you can swap in different stock attachments to match your ergonomic preference or mission requirements. The fixed version strips things back—no folding mechanism, just a clean Picatinny-rail-mounted beam that weighs just 5.5 ounces and adds 6.5 inches to your rifle's length.
Both configurations are made in the USA with mag-phosphate-finished steel parts built to last. The side-folder includes two QD sling attachment points and weighs 11.6 ounces, adding 7 inches to your carbine length and only 0.75 inches when folded—handy for vehicle storage or tight spaces. Compatible with mil-spec diameter stocks, the Alpha Series M4 Beam is engineered for shooters who demand reliability without compromise.
| Side-Folding Model | |
| Overall Length Addition | 7.0" |
| Folded Position Length Addition | 0.75" |
| Weight | 11.6 oz |
| Sling Attachments | 2 QD points |
| Material | 4140 steel, mag-phosphate finish |
| Folding Configuration | Right or left |
| Fixed Picatinny Model | |
| Overall Length Addition | 6.5" |
| Weight | 5.5 oz |
| Mount Type | 1913 Picatinny rail |
| Material | 4140 steel, mag-phosphate finish |
The side-folding version works with mil-spec diameter stocks and features a modular design, so it can accommodate different stock attachments. The fixed Picatinny-rail model mounts to any 1913 Picatinny-equipped receiver or handguard. Verify your rifle's rail system and stock compatibility before purchase.
The side-folding model is configurable for either right or left folding, so you can set it up to match your shooting preference or dominant hand.
The side-folder adds 7 inches when extended and just 0.75 inches when folded. The fixed Picatinny model adds 6.5 inches to overall length.
The side-folding model comes complete with the folding mechanism, steel clamp, and two QD sling attachment points. The fixed model includes the Picatinny-rail-mounted beam assembly. Stock tubes and other attachments are sold separately and depend on your modular configuration.
Midwest Industries
Midwest Industries
Midwest Industries
Midwest Industries
