The wrench did accomplish the small task for which I bought it. The hole in the wrench did not fit the nut on the end of the tube and one or both had to be filed enough to get it to fit. I opted to file the nut, not the wrench.



I also had a bit of a problem tightening the nut that secures the buffer tube but that was because I have no previous experience with the AR platform. After I used the wrench as a plain spanner, I realized the teeth actually fit into 3 notches and not just one. Once I realized this (from the Brownell's video) I gave the whole thing another look.



I cannot give 5 stars because there were better choices, but this was what I can afford right now.



All in all, it is an okeydokey wrench.

Worked great removing my castle nut to change out my stock. Just take your time and do it right. I'm guessing the people unsatisfied with this tool were not careful with what they were doing. Excellent fit and I would recommend this to anyone looking for a castle nut wrench.

Tool bent, deformed, and slipped on my castle nut causing damage to the threads on my buffer tube. My fault for believing an inexpensive tool could be quality. Going to buy the Magpul tool...

I am a certified AR-15 / M-16 Armorer and I work as an armorer for my police department. I purchased this as a small tool for my range bag so I did not have to carry all of my more expensive tools with me. Its not the best and if used incorrectly can cause problems. Other then that it works well and is constructed nicely. If you need something that will be used often, buy a better tool. For occasional use this works, just be patient and do it right and you will be okay.

I use this tool only for AR-15 castle nuts on pistol buffer tubes which are larger in diameter than carbine tubes. It works fine. I believe ham handed carelessness is probably responsible for some negative reviews. Brownells car15 m4 wrench is much stronger but simply wont fit over pistol buffer tubes. So if durability is a concern purchase that tool. That being said with your lower receiver in a vice and and the wrench carefully engaged in the corresponding notches in the castle nut I don't think you will have any problems with this tool. It works fine for me.

Cheap and effective, one really doesn't need to tighten a castle nut to torque specs. Tool doesn't bend the nut if used intelligently.

Decent tool for a simple removal or installation of the castle nut. It does not accommodate a torque wrench.

I bought this tool even though I read some fairly bad reviews on it. I wanted it to tighten the castle nut on an AR pistol because the regular barrel wrench wouldn't go over the receiver extension which is larger than a rifle extension. It worked like a champ and I don't know why anyone would complain about it. If you use it properly by putting the wrench down over the receiver extension and then sliding the wrench into the grooves it will line up and fit just fine. For what this wrench is made for you couldn't get anything, even at a much greater price, that would work any better.

It failed on the second rifle I was working on and damaged the castle nut. The die-stamped design is a bit flimsy for removing nuts that have been on awhile. The nut was not staked or secured with Locktite. I accidentally ordered two of these tools instead of one. Good thing as the tool failure did not hold up the project. Will see how long the second wrench last. This is the first tool problem I have ever had with Brownell's products.

It did not fit properly, too loose. Corners of one lug rounded off.

I purchased this item to replace the end plate of my M4 with an ambidextrous sling attachment. After reading the dismal reviews of some of the stamped versions and the good reviews of this wrench, I purchased this one. When removing the castle nut, which had had some kind of bonding agent added to the threads, I simply put my AR in a secure position, held the head of the wrench in place with my left hand, and tapped the end of the handle with a rubber mallet. After the third firm rap, the bonding agent broke loose and the castle nut could be easily spun back to allow removal of the stock. Worked great.

If you are an armorer or are constantly fiddling with the castle nut it may not be the best choice. However, it is higher quality than other wrenches I have seen. The metal is not polished or slick which is a good thing. It grips well and the tolerances are close. I had a stainless steel wrench/multi tool from NC Star that always wanted to slip off and eventually ended up bending. Overall for the price and quality it is a good product to buy.

Replaced commercial tube with mil-spec. Works as advertised . No fit issues with Colt replacement nut. Did not deform like other reviews stated. Had it in 2 days with standard shipping. Only performs one function but does it well.

I tried using this wrench to remove the castle nut on my Rock River collapsable stock to install a skeleton stock. It mushed and mashed like butter. Castle nut didn't move. Worthless.

I understand that if you are a full time gun smith this may not be your first choice but for the few times I will need it the tool did just what it was suppose to.The lugs lined up perfect on my Bushmaster Carbon 15.

Have heard good and bad about this wrench. But decided to try it anyway since the last 3 wrenchs failed badly to loosen the factory ring on my new M&P 15 Tac.

Happy to say it worked. Not Heavy-Duty but made of harder steel than the others and held up nicely. And most importantly.... "IT WORKED!"

Horrible stock wrench. The metal is too soft and the edges of the wrench rounded over on its first use to where it slips off the castle nut every time.

For the price, you can't beat it. Used it once and it works great. A must if your building your own gun. Easily removed and installed my DPMS stock.

For [$] it is a 5 Star tool, I think anyone with an AR should have one. The fit was excellent and it loosened the nut on my AR easily.

Fit great and nice price

Can't beat it for the money.

There are more exotic and more expensive designs out there for working with an AR/M4 stock but this one does the job just fine. It is simple, durable and cost effective. It will get the job done just as well as others out there. If you're removing/installing a new stock or sling attachment, you'll benefit from this tool.

Used this wrench twice now. Read other reviews saying it was cheap and would bend or how it didn't line up with the castle nut. Mine lines up fine and I have no idea how you would bend it if you use it for what it is made for. Great item, will be telling everyone to get one for there home use.

Works perfectly! Haven't had any issues. Already done 6 different carbine stocks with everything from Armalite to Tapco. For [$] no complaints! Mine lines up just fine and has worked flawlessly to change the sling adaptor plate.

I've used this tool to install and remove numerous stock lock nuts without a problem

You get what you pay for. I used the wrench 3 times to take the castle nuts off of ARs in order to install Magpul ASAP sling attachments. The first two times, the wrench got the job done, but on the third use the teeth of the wrench broke on the castle nut.I wasn't mad because it was only [$], but I went ahead an invested in the Brownells $80 wrench because I plan on using it for a lifetime.

Bought this for my Bushmaster Carbon 15 to add a new sling adapter. Fit the nut perfect, seems solid, very happy with it

One of three notches was off from where it was supposed to be but it did not matter. Castle nut opens and tightens without slippages and that is all I need. The hole for A2 stock is also good: no need to search for pliers to tighten up rifle length extension.

If you need to open/tighten castle nuts seldom, this tool will do the job. For continuous use there are better tools.

Pros:
-Nice grip
-quality
Cons:
-the notches don't line up, so you have to ling of lock one in and press the other notch against the rounded part of the castle nut.* now there are notch marks on the outer ring.
-the center mussel cut out dose not fit.

Got this wrench so I could remove the collapsible buttstock on my AR-15. This tool worked perfectly. Excellent quality and very well represented on the ad. I would highly recommend both the product on the brownells.com to anyone. Great price too!

This tool served its purpose for my project, which included removing the factory Bushmaster nut to install a single point sling back plate. It didn't damage the nut or bend/break in any way. It is easily worth two or three times as much.

Adequate for the price did not strip or damage gun in any way, only needed it once so for the price a good product, fit my Ruger SR22 perfectly.
Dan C

Did the job perfect. can't see how anybody can break the tool if you use it the right way.

When I first got into gunsmithing my AR-15's I purchased this tool from RRA after already having (2) RRA AR-15's and being totally satisfied, but after 1 use it bent. I didn't put more pressure on the wrench than it was supposed to have but its made out of thin metal and prone to bending. After this I purchased the DPMS wrench which is 5 times as thick. It works perfectly everytime. You may have to take a dremel tool to the tips that fit the castle nut for a glove fit, but I have now built around (15) AR platforms from .223,6.8spc,and .308 calibers and have never had a one minute of problem out of the DPMS car stock wrench. The DPMS tool also has a cut out for the A2 buffer tubes assembly as well which the RRA doesn't. The DPMS wrench is built to be ran over by an Abrams tank. If you plan on doing alot of AR collapsible stock changes do yourself a favor and get the DPMS car stock wrench. You will have less headaches!

Without a doubt not high quality at all, but got the job done for me. My only experience with it was mounting my telestock once. Taking the nut off may be a different story since it is so flimsy and cheap. Bottom line, if you plan to use it to install a new stock once it works great.

Highly disappointed. Quickly went through two wrenches. The wrench is constructed of cheap/thin metal material. [*] Expected better quality from Rock River.

My friend recently transferred to NAS Pensacola, taking his gun smithing tools with him. I needed a wrench for a one time job so didn't want to spend 75-100 dollars for it. I was a bit skeptical after reading the reviews, but it was so cheap I decided to try it. It worked great. I had to use all 180 pounds of me to get the nut off and the teeth didn't round. My brother and friends then used it with the same results. There is some signs of wear, but I say this will last at least 10 jobs. Unless your a gun smith constantly building new guns, this is the tool for you, and for the price you can't beat it.

Wasn't able to remove a stuck receiver nut with it, bent while applying torque. Heat, cold, penetrating oil didn't help on the nut. Ended up having to use a pipe wrench.

After one use, the wrench stripped off one of the gripping teeth. This caused the wrench to slip, and damage the threads. Very disappointed in the poor quality of this tool. I guess you get what you pay for.

Bought it to assemble a mil-spec carbine buffer tube. After I flattened out the working section of the wrench on a hard flat surface with a 24 oz. ball peen hammer...it did the job nicely. No marks, developed torque, Loctite 242 and a point swage will make sure the tube does not loosen up.

I needed this tool for a one time stock installation. That's about all it's good for. VERY soft metal and it's SMALL, so you can't really get much leverage on the tool. The teeth were already wearing after 1 installation. This might be something to get to throw in the range bag for a "What if" situation.

Just got this wrench to finish a build and it worked perfectly on the Mil spec tube. No idea why anyone would buy the expensive ones when this one does the job just as well. Very happy with the product.

Used mine for 3 builds now. Never had a problem causing rounded castle nuts or not being able to loosen/tigthen nuts. I don't think this would work too well for a staked on nut or a really stuck one. Handle is a bit short for placing alot of torque. I do like that it has a hole for rifle buffer tubes. Makes this somewhat versatile. For the price though, this is a great deal.

Tool appears to be of fair quality and I liked the plastic molding on the end that you would grip. However, I have an S&W M&P 15 and this tool does NOT fit the castle nut to change out the existing collapsible butt stock. Instead, I would recommend the simple hook spanner wrench to remove the castle nut for the M&P 15

I have had several of these tools and they are not a bad buy at [$] but the steel is very soft and eventually, the teeth will round off which can cause damage to the castle nut on your AR. The nut is easily replaced of course. All said, I guess you get what you pay for here.

It gets the job done.

Pretty basic tool that easily gets the job done.

However, before mine arrived, I hand tightened the castle nut on my CAR buttstock and gave a quick snug with a padded tongue-and-groove pair of pliers.

Turns out, that was all the rifle needed, and the proper wrench didn't get it any tighter. I can see this wrench being especially useful in removing a stuck nut or when working with bad threads, though.

Rounded off the castle nut, pops off of the castle nut and scratched the tube. This is on a DPMS LR308-AP4. Do not use if the nut is tight, these guns are too expensive to scratch with low quality tools.

i figured that this would be on par with the cheap wrenches from ikea furniture...WRONG! Pleasantly surprised to see how beefy this tool was. Great for people who don't need a gazillion tools to get one job done. used on UTG M4 stock and didn't damage castle nut.