I purchased this stock to upgrade the standard stock on my Ruger 556. It installed easily using a 1/8" punch as a lever to lift the locking pin enough to allow it to slide onto the buffer tube. It is somewhat heavier than my other Magpul stocks but I knew that before I ordered and for my use this is not an issue. The friction lockup is great, it removes almost all wobble when engaged, but easily disengages by lifting the adjustment lever if adjustment is needed. The design and shape of the stock with "battery storage tubes" make good and comfortable cheek rests. However, one thing I quickly noticed, the hollow tubes do amplify the buffer noise when shooting...since I am not using that feature to carry batteries, I inserted two pieces of grey 1/2" foam tubing (like small "pool noodles") cut to length, which freely slide into the hollow spaces of the stock, and seem to soak up much of the buffer sound as well weighing almost nothing (it's easy to pull them with tweezers if desired). The hollow center of the foam tube also makes a convenient place to carry a spare firing pin if needed.

The trap door storage compartment is just the right size to carry an extra 2032 battery for my Vortex Spitfire as well as a couple pair of foam earplugs.

Overall...this is a great stock with useful features.

This stock is legit solidly built. I put this on my Knights Armament SR25 in place of the existing stock and this one locks tight. No movement or wobble. Balances the rifle really well for firearms that are front heavy.

The cheek weld feels soo good!

I miss the rifle stock storage. This at least has some storage for batteries or notes for zeroing.

Went on extremly eazy with the supplied "dummy round pry thing", fits perfect, no noise, no slop. I have a beard and nothing catches or pulls on my hair. Couldn't have asked for a better stock, exactly what I wanted.

This stock is awsome, comfortable to shoot, easy to maneuver when doing shooting drills, great product, and of course, its a Magpul.

This is the second ACS stock I have purchased. Excellent cheek weld and the compartments are useful. I keep a sealed lense cleaning package in the bottom compartment for my red dot and magnifier and two spare AA batteries for the sight on one side and two back back up batteries for the attached rail light on the other side tube. Nice to have everything with the gun and not somewhere else when you need it most.
When you order it, ask if it comes with the QD swivel mount or not. First one I got did not, had to order one seperatly. Second one I ordered did come with one and not knowing that it came with one, I ordered one that I don't need and have to send it back.

Was easy to install then expected. Lots of storage and no movement. I wrapped xtra ammo, bolts and batteries in foam to keep in place and helps cut down on the noise. Well worth the money.

I have a S&W M&P-15 and I was looking for the bigger cheek weld and something better than the cheap plastic stock that came with it. I wanted something rugged. I ordered hoping it wasn't just another piece of plastic I could break. Very solid construction, great fit and super simple to put on (even I can). Definitely recommend as a replacement for any one that you have.

The original Mil-Spec carbine collapsible stock left three main things to be desired: wobble, cheek weld and length of pull (for me) was too short. All three made sight alignment difficult.

The Magpul ACS solved these issues. As the other reviewers have noted, the lockup is solid, I don't think it moves any when the cam-lock is engaged. The cheek weld is cut at just the right angle for sight alignment, and the extra length gets the receiver out there where I like it w/o body armor and vest equipment.

You will trade up a little in weight from the OEM stock, and it's good to note that this model does not have slots for top-mounting a sling for patrol carry.

However- the Magpul ACS AQ swivel (available here at Brownells) does move the center of gravity up to give you a higher attachment point.
If sling options are a priority you might want to check out the other Magpul stocks. For me, the improvements in the ACS are worth the trade for the lower sling mount positions.

The storage is ample and that the tubes are accessible from the rear (instead of the front, as in another design I tested recently) is a much better access point. Storage covers close securely and the tubes are probably water-resistant for shallow depths.

It looks like you'd be able to stash about 6 or so extra rounds in the little trap door area, which might be a handy thing. I haven't explored the possibilities of this little space

Finally Magpul offers more options for the butt plate if more thickness or increased "grab" is desired at the back end, but the one that comes with this is a big improvement over the hard, flat original.

I have this stock on my patrol rifle. It locks up tight and provides a superb shooting platform for my AR.

This is a great telestock for those looking for a better cheek-weld, as well as a solid feel to a carbine with a longer or heavier fore end. I used it on an 18" barreled set-up that I Cerakoted in FDE, and the color-match is perfect too. I even coated the Milspec extension tube, and had no issues with fit or function. The protected plunger latch is a nice feature, as is the locking latch common to the CTR. The rubber butt pad is another nice feature too. It survived the "mortaring" malfunction clearance technique in -18 C (just below zero F), when the AAC buffer gave us problems due to a weak and non-functional recoil spring. This is a pretty tough carbine stock, as we have seen other brands break when doing that malf clearance in cold weather. Be advised that this is much longer than standard carbine stocks for sure, so you will have plenty of stock length if you are taller, while still having ideal compactness when collapsed if you are shorter.

I popped this on my Ruger 556 and it works great. No wobble at all, snug, solid, and the weight balances out the front-heaviness of my troy quad rail. Plenty of battery storage in the two side tubes. The compartment is a bit on the small side, but I don't plan on putting anything in there but maybe a bore snake.

Overall, a very solid addition to your AR. About the only thing that I'd recommend is maybe going with the CTR if you've got a lighter rifle.

I purchsed the Magpul ACS Stock for my Armalite AR-10(mil spec:1.145); fairly simple to install, but recommend using a small punch or screwdriver versus the "dummy rounds" that were sent with the unit; the Friction Lock design is GREAT!!; even a more secure fit than the original butt stock, that came with the rifle. I HIGHLY RECOMMEND this product ! ! !

This stock will increase your accuracy of your rifle. This item is very well designed. Also like the extra battery storage areas.

Its an improvement over the CTR. The built in cheeck weld feels nice and puts my eyes inline with my Eotech perfectly. It also counters the weigth of forward heavy GPU operated SBR carbines nicely with the added ability to store 6 additional CR123 batteries for my Eotech and surefire light.

This stock is perfect. It holds six 123 batteries (that's reload for both my EoTech and Surefire, plus two more - do you really need more?), and I really dig the extra storage compartment. This stock is sleek, with no sharp edges or angles, allows a good, solid cheek weld, and has several sling attachment options. Additionally, the friction adapter really locks it in place with no "wobble" like so many other AR stocks. In my opinion, the best AR-15 stock out there. Highly recommended.

"Drop in" is an understatement. It can be installed faster than you read that sentence! Positive stops, room for small items, nice cheek weld. It puts my dot dead on the top of the front sight every time. Worth the money

Picked this up for one of my custom builds. Not many people take into account what the material is used on the butt stock. I prefer a material that will grip your shoulder well and conforms to the operator ... basically a molded rubber pad over the end. This is just as important as getting the right sized shoes.

The ACS Stock has a very nice butt pad. It grips to the operator well and makes shouldering the rifle more comfortable and can be held in place easier. The end caps for the storage compartment are rubber and are attached to the stock ... this is a plus so you don't have to feel around for them if you drop it in the dark. The cheek weld is nice and comfortable and clears the charging handle with ease.

The stock is easy to install if you read the instructions. You cannot simply pull the rocker switch down and slip it on. The instructions show you where you have to insert either a screw driver, bullet or something else underneath the rocker leaver to pry it up to remove. Not necessary a big deal, but it isn't coming off in a hurry. It does lock up tight and is overall a very nice stock.

There are only two things that needs improvement. The cheek weld area on the stock I received was not finished very well. It still had rings from were the plastic was in the mold. I had to take some sand paper and finish it off smooth ... if your paying $100+ for a stock this should of already been done. The other issue is unlike the VTOR series stocks; the ACS does not have any plate on the bottom to protect the stock when it is on a tri-pod. The bottom of the stock has a hollow area that looks like a monopod attaches there, but is easy beat up when shooting prone ... a pop in metal plate would of been a great asset there.

I replaced my Vltor Emod stock with the Magpul ACS and never looked back. Fit and finish, it wins hands down against LMT Sopmod and the Emod. Everyone asks about it, and everyone wants one once they try it. I got the first one in black and just got a second in Flat Drk Earth. I am about to purchase a third in OD green. I guess, I now kinda get why women have so many shoes even though they only have one set of feet. I only have one AR-15 (soon to be two), but I need all the ACS stocks, in all the different colors, and this particular one cannot be beat. It's cheaper than Magpul's own UBR stock, yet it has all it's fit and function, plus more!

now i can build an AR-15

Great stock! Couldn't be happier with it. Was already a huge Magpul fan, and they continue to never disappoint. They took the best aspects of both the CTR and UBR and put them together into this beautiful thing. Locks into place easily and stays there with the friction lock, no "play" at all. I paired mine with Magpul's ASAP end plate and it works great.

The only recommendation I will make is that if you use the battery compartments, stuff a cleaning patch in after inserting the batteries to prevent any rattle. Other than that, it's perfection.

Same slope on the cheek wield as the UBR but with extra battery storage, plus lighter and half the price!!!! what's not to love...

I found the ACS to be superior to the SOPMOD or any of the other copy cat stocks. Like Magpul's CTR you get a tight fit to your buffer tube. Same quality materials that Magpul is known for. Better yet the pricing is fair.

Comfort, balance and the quality you come to expect, plus the great cheekweld and storage that was missing from the great "CTR".

Puts all other M4 stocks to shame. Far better than the SOPMOD/Crane stock, VLTOR, or any other "high speed" or issue stock. After 17 years in service, multiple combat tours as an Infantryman, and seeing every latest/greatest product, it's refreshing to see an actual substantial improvement in a piece of equipment.