Your basket is empty.

Basket

Help and contact

Free standard delivery over £199

100-day return policy

Newsletter

Sale

Over 300,000 customers - we say thank you!

4.93/5 "Very good" (1400+ reviews)

40,000+ products for hunting and shooting sports

BROWNELLS
CAR-15/M4 BUTTSTOCK WRENCH

050806006638 080000670

Description
Ratings (13)

Solidly Engages The Receiver Extension Nut For Easy Installation & Removal Of Carbine Buttstocks

Dedicated wrench has four precision-machined teeth that ensure full, non-slip engagement of all four notches in an M4-type receiver extension nut for easy removal and installation of collapsible carbine buttstocks. Transfers all the torquing force to the nut for fast tightening or removal without risk of damage to nut, extension tube, or receiver caused by the wrench slipping. Includes the handy add-on features of our universal M4 buttstock tool: pry blade/screwdriver, ½" square torque drive opening, fixed stock receiver extension remover, and a convenient hole in the handle for hanging the wrench on a pegboard. Heavy duty steel construction, machined from a single piece of .312 thick steel, with a durable black oxide finish.

SPECS: Steel, hardened, black oxide finish. 7-1⁄8" (18.1cm) long. Fits current-model M4-type receiver extension nuts with four square notches.

More...

Customer ratings for BROWNELLS M4 BUTTSTOCK WRENCH

Number of ratings: 13
From brownells.com: 13
Average rating: 4.5

M4 Buttstock Wrench (07/08/2009)

Got one. I work on lots of AR's. I like the four point fit on the stock nut. However, difficult to put on and handle is short. Hard to get leverage.

Full engagement is a big plus (19/08/2009)

Full engagement is a big plus, and Â½ inch torque wrench cut is nice to tighten to spec, easy to stabilize with torque wrench.

Miossi Gun Works LLC

Good wrench with limitations (16/10/2010)

Excellent wrench with 100% engagement on all 4-slots on the castle nut. Limitations are when working on a rifle with a Magpul ASAP on it. The wrench cannot fully engage the castle nut because of interference with the ASAP plate.

I like this wrench to break loose a heavily staked castle nut because it engages all four contact points.

Great Tool Must Have (05/09/2011)

I teach AR-15 armorers classes. Great tool. Handle needs to be longer without the sharp end. Will break staked castle nuts and red loctite loose. A must for an AR-15 Armorer.

Best AR buttstock wrench available... (07/02/2012)

This is the best AR buttstock castle nut wrench available, bar none. Extremely well built, heavy duty, 4 point wrench. Probably overkill for a one time use type of wrench, but if you want the best here it is. Requires removal of the collapsible stock to use the wrench on the castle nut, but that's not a big deal. The open side of the wrench will slide down the buffer tube but not over it, so you have to pull the butt stock off the tube first. If you are a gun builder or just want the best tools in your box this Brownell's wrench is the right wrench for you. If you only need to use the wrench once then one of the cheaper Tapco would probably be enough.
Highly recommended.

Great tool (02/07/2012)

Great tool. Handle a little short. Works best with an added extention.

Great wrench (13/08/2012)

This Brownells carbine wrench is the best I have ever used. Being an M16/M4 armorer for years I have used a few. This one is strong, and has not failed. I had one I thought would never come off without heat or worse, and my new wrench did the job. Spendy, but worth the one time cost.

Great Tool (18/09/2013)

We work on rifles every day, after wearing out some other tools we came across this one. Wish we would have found it earlier. Makes the job much easier. Only down side is having to take stock off but not a big dea.

Buttstock installation must (05/12/2013)

If you're building ARs, you need this wrench. Put down your crescent wrench and slip-joint pliers and use this instead.

does not work with all buffer tubes (23/12/2014)

This wrench does not fit over all buffer tubes. The phase 5 buffer tube does not allow for the wrench to slide down to the castle nut. This is a nice tool but is a little sharp on the hands. All in all it is well made, just the nature of its construction does not make it very versitile.

Right tool for the job! (09/01/2015)

If you really want to do the job right the first time and not risk damaging the finish to your valuable investment then this is the only product worth looking at. Yes, costs more than 2X the budget wrenches but wow, it is so super-solid you will have no qualms about using this on your firearm. The 4-tooth design locks squarely on the castle nut and make removal of a stubborn castle nut safe and easy. Could use a longer handle, but I fit a length of pipe over the end for leverage on a very tightly locked on nut and voilÃ¡ -- no damage to the nut or tube. Not even a mark on the castle nut where the wrench teeth fit. Glad I bought it and did it right the first time. Thanks Brownells!

3rd time is the charm (03/08/2015)

This is my 3rd wrench. Too bad it wasn't the first. Fits both Stag and DPMS nuts. It's short, but I think that is by design. Longer might lead to over-torquing. By being short, it encourages me to use a torque wrench for leverage.

The right tool for the job (01/03/2017)

Very thick steel. This is what you want to remove those castle nut especially those that were staked by Colt. Can also be used on rifle receiver extension plus what's nice is there's a 1/2" drive for torque wrench. Not all receiver extension wrenches will have it. I really liked the 4 notches of the wrench how thick they were made really extending more on the notches of the castle nut. Get it and you'll be glad you did!

Read 13 more ratings on brownells.com

94.9 94.9 1 GBP

Product no.: 080000670
BROWNELLS M4 BUTTSTOCK WRENCH
Mfr Part: 100254 050806006638 Dedicated wrench has four precision-machined teeth that ensure full, non-slip engagement of all four notches in an M4-type receiver extension nut for easy removal and installation of collapsible carbine buttstocks. Transfers all the torquing force to the nut for fast tightening or removal without risk of damage to nut, extension tube, or receiver caused by the wrench slipping. Includes the handy add-on features of our universal M4 buttstock tool: pry blade/screwdriver, ½" square torque drive opening, fixed stock receiver extension remover, and a convenient hole in the handle for hanging the wrench on a pegboard. Heavy duty steel construction, machined from a single piece of .312 thick steel, with a durable black oxide finish.

94.9 GBP 74 £94.90 *

Delivery time approx. 7-14 days.
More than 10 pieces in USA warehouse

Specs: Make: AR-15

Add to shopping list

Ask question

Details