The M1S90 to M4 buffer tube adapter is a modification that allows gun owners to attach an M4-style adjustable stock to a Benelli M1 Super 90 (M1S90) shotgun. This upgrade provides more flexibility, better ergonomics, and customization options for firearm enthusiasts.
Originally, the Benelli M1S90 comes with a fixed stock, which limits adjustability and makes it less adaptable for different shooters and scenarios. However, by installing this buffer tube adapter, users can enjoy the benefits of an adjustable M4 stock, making the shotgun more versatile and comfortable to use.
Understanding the Benelli M1S90 Shotgun
The Benelli M1 Super 90 (M1S90) is a semi-automatic shotgun that has been widely used in law enforcement, military, and sporting applications.
Key Features of the M1S90
- Semi-automatic inertia-driven action – Reliable and lightweight.
- 12-gauge chambering – Common and powerful ammunition choice.
- Durability and dependability – Used in tactical and self-defense roles.
- Fixed stock design – Limits adjustability and customization options.
While the shotgun performs exceptionally well, many shooters find the fixed stock restrictive. This is where the M1S90 to M4 buffer tube adapter becomes useful.
What is an M4 Buffer Tube?
Before understanding the adapter, it’s important to know what an M4 buffer tube is.
Purpose of a Buffer Tube
A buffer tube, also called a receiver extension, is a cylindrical component that houses the recoil spring and buffer system in AR-15/M4-style rifles. While the M1S90 does not use a buffer system like AR rifles, the buffer tube serves as a mounting platform for an adjustable stock.
M4 Stock Advantages
- Adjustability – Multiple length settings for different shooting positions.
- Comfort – Allows shooters to adjust the stock length to fit their body size.
- Customization – Compatible with various M4 stocks, allowing personal preference.
- Tactical Utility – Offers better adaptability for different shooting environments.
Since M4 stocks are widely available and customizable, many firearm owners prefer them over fixed stocks.
How the M1S90 to M4 Buffer Tube Adapter Works
The M1S90 to M4 buffer tube adapter serves as a conversion piece that allows an M4 buffer tube to be mounted on the Benelli M1S90 receiver.
Functions of the Adapter
- Replaces the fixed stock attachment point on the M1S90.
- Provides a stable mounting platform for an M4-style buffer tube.
- Allows the installation of adjustable M4-style stocks.
- Enhances ergonomics and shooter comfort.
By using this adapter, the shotgun can now accept a collapsible or fixed M4-style stock, improving handling, maneuverability, and shooting experience.
Benefits of Using the M1S90 to M4 Buffer Tube Adapter
Adjustable Stock Compatibility
Unlike the fixed stock of the M1S90, an M4-style stock can be extended or collapsed to fit different shooting needs.
Better Comfort and Ergonomics
- Adjustable stock provides a custom fit for different shooters.
- Easier to use in tactical situations or close-quarters combat (CQC).
- Lightweight options available to reduce overall firearm weight.
Increased Customization
The adapter allows you to use a wide variety of M4-style stocks, including:
- Tactical stocks with storage compartments.
- Padded stocks for recoil reduction.
- Slim stocks for lightweight handling.
Improved Tactical Advantage
For law enforcement, military personnel, and home defense users, an adjustable M4 stock provides better adaptability in different situations, such as:
- Compact storage – Collapsible stock makes storage and transport easier.
- Quick adjustments – Shooters can change stock length based on gear or armor.
Installation Guide for M1S90 to M4 Buffer Tube Adapter
Installing the adapter requires basic tools and mechanical knowledge.
Tools Required
- Screwdriver
- Punch tool (if needed for pin removal)
- M1S90 to M4 adapter
- M4-style buffer tube
- M4-style stock
Step-by-Step Installation Process
Remove the Existing Stock
Unscrew the stock from the M1S90 receiver.
Install the M1S90 to M4 Adapter
Attach the adapter securely to the receiver.
Attach the M4 Buffer Tube
Thread the M4 buffer tube onto the adapter.
Install the Adjustable M4-Style Stock
Slide and lock the M4-style stock onto the buffer tube.
Check Stability and Fit
Ensure the setup is tight and secure before use.
Things to Consider Before Installing the Adapter
Compatibility
Not all M1S90 models may fit every adapter, so ensure you get an adapter specifically designed for your model.
Legal Compliance
Modifying a shotgun’s stock can sometimes affect firearm regulations.
- Check local and federal laws to ensure compliance.
Material and Durability
Choose adapters made from high-quality aluminum or polymer for durability and strength.
Structural Integrity
Incorrect installation could affect the shotgun’s balance or performance. Ensure:
- The adapter is secured properly.
- The stock fits snugly and does not wobble.
Popular Brands Offering M1S90 to M4 Buffer Tube Adapters
Several manufacturers produce high-quality adapters for this conversion. Some reputable brands include:
- Mesa Tactical – Known for high-strength aluminum adapters with a solid lock-up.
- GG&G – Offers reliable tactical upgrades for shotguns.
- Other brands – Various aftermarket companies produce similar adapters, but quality varies.
Price and Availability
Cost Range
- Entry-level adapters: $50 – $80.
- High-end tactical adapters: $100 – $150+.
Where to Buy
- Firearm accessory retailers.
- Online firearm parts stores.
- Directly from manufacturers like Mesa Tactical or GG&G.
Conclusion
The M1S90 to M4 buffer tube adapter is an excellent upgrade for Benelli M1 Super 90 owners looking to improve adjustability, ergonomics, and customization.
By replacing the fixed stock with an M4-style adjustable stock, shooters can enjoy:
- Better comfort and fit.
- Enhanced tactical utility.
- A wider range of customization options.
Whether you’re a tactical shooter, law enforcement officer, or home-defense gun owner, this adapter conversion provides a practical and effective way to upgrade your M1S90 shotgun.
FAQs
Can I install an M1S90 to M4 buffer tube adapter without gunsmithing?
Yes, most adapters are designed for simple installation using basic tools, but some may require minor fitting.
Will using the adapter affect my M1S90’s recoil?
It depends on the stock used; some M4-style stocks have built-in recoil pads or buffers that help reduce felt recoil.
Is an M4 buffer tube adapter legal on the M1S90?
In most cases, yes, but local firearm laws vary, so check regulations before modifying your shotgun.
Does this adapter work with both commercial and mil-spec buffer tubes?
Some adapters are mil-spec only, while others fit both types—check compatibility before purchasing.
Can I switch back to the original stock after installing the adapter?
Yes, the modification is reversible, allowing you to reinstall the factory stock if needed.
