BROWNELLS AR-15/M16/M4 Stock Installation Tool

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BROWNELLS · AR-15/M16/M4 · STOCK TOOL
Work on castle nuts and fixed stocks with the right engagement
The compact steel tool covers typical tasks on M4 collapsible stocks and fixed AR stock systems. Interchangeable round and square pins fit different castle nuts; the 1/2″ drive accepts a separate torque wrench.
Purchase check: Inspect castle nut groove and stock system


Honest assessment
The strength lies in specialization on stock work. It is not a full armorer’s wrench nor a torque wrench. A clean-fitting, squarely applied pin is more important than extra leverage.



Fits well if …
you work on standard AR-15/M16/M4 stock systems
you encounter round and rectangular castle nut grooves
you want to cover fixed and adjustable stock systems with one tool



Less suitable if …
you want to work on barrel nuts or muzzle devices
your stock system has proprietary, unusual geometries
you expect a tool with its own torque limit




Practical features and benefits


Interchangeable pins Round and square pins cover older and newer nut grooves.

1/2″ drive Allows connection to a separate, calibrated torque wrench.

Fixed stock aid Screwdriver blade and barrel nut area extend the use.

Compact design Less bulky than a full multi-purpose armorer’s wrench.



Limits and avoid bad purchases

No barrel nut or M
Firing tool.
The 1/2″ socket does not measure torque.
Do not loosen peened or glued nuts with uncontrolled force.
Check proprietary systems precisely before applying.

Technical data with practical relevance

Compatibility AR-15/M16/M4 stock and receiver extension hardware according to functional description.

Material steel, black.

Length 7″ / approx. 17.8 cm.

Identity SKU 080000291 · GTIN 050806107236.

Stock 0, reorder enabled.

Delivery time 1–3 working days.

Scope of delivery
One BROWNELLS stock mounting tool, one round pin and one square pin. Torque wrench, hex key, spare pins, stock and buffer tube are not included.

Application and safety
Weapon fully unloaded, checked and stably supported.
Check actual groove shape and attach matching pin without play.
Apply tool perpendicular and fully into the groove.
Take torque values and locking procedures exclusively from the component manual.
Check pins for cracks, bending and rounded edges after stress.

Frequently asked questions
Does the tool fit round and rectangular grooves? Yes, both pin shapes are included and interchangeable.
Is a torque wrench integrated? No, the 1/2″ opening accepts a separate tool.
Does it replace a full armorer’s wrench? No, it is specialized for typical stock work.
Can I work on fixed stocks? Screwdriver blade and barrel nut area are intended for this; the specific geometry must fit.
What to do with a tightly stuck nut? Professionally check locking, peening and component condition, do not simply increase lever force.

Black-Raptor conclusion A versatile but clearly defined AR stock tool – useful with the right groove and controlled application, not a universal tool for all firearm assemblies.