Midwest Industries Alpha M4 Beam Side Folder Adjustable 1913 Stock
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Product description
MI Alpha M4 Beam Adjustable 1913 Stock – Side-Folding Version
The Midwest Industries Alpha M4 Beam Adjustable 1913 Stock offers a versatile and durable solution for AK47 and other firearms with a 1913 stock adapter. This side-folding stock is designed with a heavy-duty folding mechanism constructed from 4140 steel, ensuring a solid lock-up in both open and folded positions. The modular design allows users to attach their preferred Mil-Spec AR15 stocks, enhancing adaptability and comfort.
This stock includes 2 QD sling attachments and a curved top to reduce wobble from the skeletonized beam. Made in the USA with a mag phosphate finish on steel parts, it combines reliability with a sleek appearance.
Fits 1913 style rails, minor fitting may be required.
Product Highlights:
- Heavy-duty side-folding mechanism constructed from 4140 steel
- Full-length locking lug for maximum strength
- Solid positive lock-up in both positions
- Steel clamp with large surface engagement
- Configurable for right or left folding
- Modular design can accommodate different stock attachments
- 2 QD sling attachments
- Compatible with Mil-Spec diameter stocks
- Curved top to mitigate wobble from skeletonized beam
Specifications
- Brand: Midwest Industries
- Model: Alpha M4 Beam Adjustable 1913 Stock (Side-Folding)
- MPN: MWMI-ALPHA-M4BSF
- Material: High-strength polymer, aluminum, and steel components
- Finish: Anodized, Black; Steel parts are mag phosphate finished
- Weight: 11.6 oz
- Dimensions:
- Adds 7.0” to overall firearm length
- Adds 0.75” to the length of the firearm in the folded position
Customer reviews 1
Verified buyerQuestions & Answers 4
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Midwest Industries Alpha M4 Beam Adjustable 1913 Stock work/Fit with SB Tactical SBA5 Pistol Brace?
Mark · Jul 27, 2025AT3 Support Team — I'm afraid the Midwest Industries Alpha M4 Beam Adjustable 1913 Stock and the SB Tactical SBA5 pistol brace are not directly compatible with each other.
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Thanks for reaching out Yes it is Thanks
Kevin Freeman · Jan 15, 2025 -
What stock do I need for this and what cheek riser also do I need??
Jesus · Nov 7, 2024AT3 Support Team — You can use any standard AR-15 carbine stock with the Midwest Industries Alpha M4 Beam, and it comes with an adjustable cheek piece for comfort. If you require more height, consider adding an aftermarket cheek riser compatible with your chosen stock.
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Does this stock work on a MPA Defender with pickatinny rail on the back?
Jose Gonzalez · Nov 7, 2024AT3 Support Team — Yes, the Midwest Industries Alpha M4 Beam Side Folder Adjustable 1913 Stock is compatible with the MPA Defender as long as it has a Picatinny rail on the back. This setup allows you to utilize AR-15 stocks and provides a solid folding mechanism for enhanced portability.
Warranty & returns
Backed by Magpul Warranty!
Magpul Warranty Information
If you ever experience an issue with a Magpul product at any time, regardless of where it was purchased, please contact us directly and we’ll do everything reasonable to help you.
To make a return, please take the following steps:
- BEFORE returning any products, please contact us first to receive an RMA number (Return Merchandise Authorization) and prominently write it on the outside of the package. Packages will not be accepted without an RMA.
- Include a note with your name, shipping address, phone number and email, RMA number, and reason for the return (including, if applicable, information about the firearm, ammunition, and usage environment for defective returns). Do not send ammunition.
- Wrap the item with quality padding and place it in the original packaging or in an appropriate box for shipping.
- A UPS shipping label will be provided in your shipment. If using the original packaging, remove or cover the original shipping label. Tape the preprinted return shipping label to the outside of the box. Drop package at an official or authorized UPS drop-off location.
- All refunds will be applied to the credit card used for the original purchase. You should allow one to two billing cycles for the refund to appear on your statement.
Disclaimer: Manufacturer’s warranty is subject to change without prior notice.
90-day no-hassle returns
The AT3 Tactical store has a 90 day no-hassle return policy for products in good condition. You can view the full details of our return policy here.
If you encounter an issue or defect with a product after 90 days of your purchase, you can refer to the manufacturer for a warranty claim. Their policies are below.
