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B5 Systems

Ar-15 Enhanced Sopmod Stock Collapsible Mil-Spec - Ar-15 Sopmod Stock Collapsible Mil-Spec Coyote Brown

Our editorial team reviews specifications, product data, and field-use information to keep pages accurate.

Reinforced Polymer

Stock fits M4-type receiver extensions

Improved Cheekweld

For added comfort and consistency

Two Waterproof

Storage compartments hold 2 AA

Streamlined Contours

Help resist snagging on gear

Sure-grip Stock

Latch supports easy length-of-pull adjustment

$93.99
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SKU: 100028999

Overview

Built for M4-type receiver extensions, this reinforced polymer stock is aimed at shooters who want a more consistent cheekweld and a straightforward adjustable setup. It includes two waterproof storage compartments sized for 2 AA or 3 CR-123 batteries, giving hunters and field users a place to carry small essentials within the stock itself. Streamlined contours are designed to reduce snagging on clothing, gear, or vegetation, while the Sure-Grip latch and anti-slip rubber recoil pad support secure handling and length-of-pull adjustment. A black stainless steel QD swivel mount and two molded sling slots add carry options for a practical, mission-ready setup.

Why Hunters Choose the B5 Systems

Improved Cheekweld

Supports more consistent shoulder placement

Two Waterproof

Storage compartments keep small items

Fits M4-type

Receiver extensions for compatible AR-15

Streamlined Contours

Help reduce snagging on gear,

Sure-grip Stock

Latch allows convenient length-of-pull adjustment

Key Features

  • Reinforced polymer stock fits M4-type receiver extensions
  • Improved cheekweld for added comfort and consistency
  • Two waterproof storage compartments hold 2 AA or 3 CR-123 batteries
  • Streamlined contours help resist snagging on gear or vegetation
  • Sure-Grip stock latch supports easy length-of-pull adjustment
  • Anti-slip rubber recoil pad helps secure the weapon to the shoulder
  • Includes a black stainless steel QD swivel mount and two molded sling slots

Best Used For

  • Hunters wanting a stable cheekweld on an M4-type receiver extension setup
  • Users needing onboard storage for AA or CR-123 batteries in the stock
  • Field carry where streamlined contours help reduce snagging on clothing or brush
  • Shooters who prefer quick length-of-pull adjustment with a Sure-Grip stock latch
  • Operators using sling setups with QD swivel mount and molded sling slots

Specifications

Battery Capacity2 AA or 3 CR-123 batteries
ColorCoyote Brown
Fits M4 Type Receiver Extensionstrue
Improves Cheekweldtrue
Length Of Pull Adjustmenttrue
Materialreinforced polymer
Military UseCurrently employed by the U.S. military
Qd Swivel Mountblack, stainless steel
Recoil Padanti-slip rubber recoil pad
Sling Slotstwo molded 1A 1/4" wide sling slots
Snag ResistanceStreamlined contours resist snagging on clothing, equipment, or vegetation
Stock LatchSure-Grip stock latch
Storage CompartmentsTwo waterproof storage compartments
Waterprooftrue
Waterproof Storage For Small Itemstrue

Pros

  • Improved cheekweld supports more consistent shoulder placement and comfort.
  • Two waterproof storage compartments keep small items or batteries protected.
  • Fits M4-type receiver extensions for compatible AR-15 setups.
  • Streamlined contours help reduce snagging on gear, clothing, or vegetation.
  • Sure-Grip stock latch allows convenient length-of-pull adjustment.
  • Includes a QD swivel mount and two molded sling slots for carry options.

Considerations & Trade-offs

  • Designed for M4-type receiver extensions, so fit is limited to compatible mil-spec setups rather than every AR-style platform.
  • The integrated storage compartments are useful for small items, but they add bulk compared with a simpler stock.
  • Built-in battery storage is sized for 2 AA or 3 CR-123 batteries, which may not suit larger accessory loads.
  • The reinforced polymer construction and added features prioritize function, but they also make this a more specialized stock than a minimalist option.

Suggested Comparisons

  • AR-15 stock accessories
  • M4-type receiver extension stocks
  • Adjustable rifle stocks
  • Sling and storage stock accessories

Suggested Accessories

  • QD sling swivel
  • Rifle sling
  • Battery storage organizer
  • Rubber recoil pad

Frequently Asked Questions

What type of receiver extension does this stock fit?

It fits M4-type receiver extensions.

Does this stock provide storage?

Yes. It has two waterproof storage compartments running the length of the stock, and the description says they hold 2 AA or 3 CR-123 batteries.

Is the cheekweld different from a standard stock?

The product description says it offers an improved cheekweld designed for increased comfort and consistency.

What sling attachment options are included?

It includes a black stainless steel QD swivel mount and two molded 1A 1/4" wide sling slots.

What finish or color is this stock?

The title identifies it as Coyote Brown.