It seemed like first Key Mod, and then M-LOK, rails killed the quad rail. But lately I’ve been seeing a resurgence, and they’ve been popping up on builds again. I suspect it’s due to a mix of guys doing retro GWOT builds, and the influx of police surplus rifles. The later often are equipped with barrels with Front Sight Bases (FSB) and or carry handles.
I only have a couple quad rails on some clone builds, and hadn’t messed with them a lot. Strike Industries recently sent me their new M4 Quad Rail Handguard to check out though, so it was time for me to give them another shot.
The Strike M4 Quad Rail Handguard
The Strike M4 Quad Rail Handguard is made to go on a carbine length gas system barrel with a Delta ring assembly and front sight base. They use a patent pending mounting system to provide easy drop in installation and removal. No modifications are necessary to your gun, and you can swap it back at any time.
The rails are made from aerospace grade aluminum with a black anodized finish. The have Mil-spec Picatinny rails at the 3, 6, 9 and 12 o’clock positions. They give you both space and positioning options for mounting lights, lasers, foregrips or whatever else you might think you need.
The side, and top rails extend past the forward handguard retaining ring to the FSB. That gives you even more rail space to work with than a typical drop in rail. There are also two QD Sockets, located at 3 and 9 o’clock rear positions.
The M4 Quad Rail measures 8.49 inches in length, 2.20 inches in width, and 2.38 inches in height. It weighs 11.60 ounces. MSRP is $159.95. That’s competitive with a lot of handguards on the market. When you factor in that this is a drop in for older AR’s it actually saves you money. You don’t have to buy a low profile gas block, or new barrel, to mount something like an M-LOK free float handguard. It’s saving time as well since you aren’t doing those parts swaps. Plus you get to keep the rugged FSB, either as your primary sighting system, or as a back up to optics.
Donor Gun
I rummaged through my gun safe for an appropriate donor gun and stumbled on to the perfect candidate. This was an SBR build that was kind of thrown together with random parts from my parts bin. It’s a Bad Attitude Department M16A2 marked lower with a basic A2 grip and CAR stock. I initially used it on a Micro M16A2 build with a 7.5 inch barrel. Although I still run that upper now and then, I had a spare 11.5 inch PSA flattop upper siting idle. That length was more suited to general use so it lives on this lower. I dropped a surplus A2 carry handle on it and have been running it without optics. It’s a handy, simple gun and seemed like the right vibe for a quad rail.
Installation
The Strike Quad rail kit comes with an upper and lower handguard, a front barrel clamp, a T27 and T20 L wrench, and a tube of blue Loctite. There’s a warning and instruction card, but the card basically just says don’t be dumb and work on loaded guns. There wasn’t actual installation instructions and I didn’t see anything on their website either. With that said, it was fairly straight forward once you look at the rail.
The first step is to dissemble the rail by removing all of the screws. You’ll end up with two front bracket pieces, and the the upper and lower rails. The front bracket secures around the gas block portion of your front sight base. The bracket is locked in by two screws at the top and two at the bottom of the bracket. Once that’s installed you simple tuck the flange of the rear of the rails into you Delta ring assembly. Then line the extended portion of the side rail on the upper half of the rail assembly with the bracket you just installed.
I dropped my front screws in loosely, then added the bottom rail piece and got everything aligned before I added my side screws and tightened everything down. You’ll note that the rail doesn’t engage the forward handguard retainer at all. It bypasses that and locks onto the FSB bracket instead. This makes for a much more solid lockup than most drop in rails. Those typically simply replace the factory handguards and tuck into the handguard retaining ring.
Now, I will say it took a little bit of wiggling to get the rails lined up. I might have used a little bit of judicious malletization to get things just so. It’s okay, the Strike rails took it without issue, and once everything was straight it snugged down nicely. Once in place the rail assembly is rock solid, with no movement that I could detect whatsoever.
Feel and Function
I like the looks and feel of Strike’s Quad rail. Since it connects at the FSB, it has a bit more real estate than other drop in rails. While it is a quad Picatinny set up, it’s not overly bulky and doesn’t have a lot of sharp edges. I could, and likely will, run this without rail covers. As noted under installation, these rails are solid. There is no play to them whatsoever.
I also liked that it doesn’t interfere with the forward sling swivel or bayonet lug. On my 11.5 inch upper the bayonet lug is superfluous anyway. But if you were running a 14.5 barrel you’d still be able to use it. Now, the rail does have the QD sling mounts on either side of the rail. So depending on your set up you may not need the front sling swivel anyway. But I still like having it as an option.
I Have Rail Space, I Need To Use It!
Well, yes and no. It is nice having plenty of space available to mount whatever you need. But honestly, on a tight SBR set up like this I don’t have a lot I wanted to add. There was plenty of space for my Steamlight TLR-1. I attached it on the left side rail, positioned so that I could easily activate it with the thumb of my support hand. Other than that the only thing I added so far was a short TVG foregrip from CAA.
Strike Industries’ M4 Quad Rail Handguard is a very functional upgrade for older AR’s with sight bases. Or for folks who are still doing FSB builds like I am. With the influx of police surplus that’s been hitting the market the past year or more there are a ton of reasonably priced AR’s out there. Most are still rocking basic M4 furniture. The Strike Quad Rail is a great way to upgrade those older guns, or one that’s been gathering dust in your gun safe, without doing an upper rebuild. For this or a myriad of other AR products, not to mention other platforms, check out the Strike Industries web page.
More Strike Industries Content on TTAG:
- Strike Industries Sentinel Rifle piece (Primary Arms collaboration)
- Strike Industries Cobra Tactical Fore Grip review
- Strike Industries Mega Fins handguard review
Good review, thank you.
But no thank you. Most accessories of interest or use to me come “native” M-Lok, and for those that don’t thr adapter is simple, light and inexpensive.
Cool build, but not really my thing.
The recent rise of the early GWOT nostalgia thing doesn’t make much sense to me except as some sort of marketing push.
Tiny market of us GWOT vets and those who followed firearm trends just post AWB. Honestly will probably get a cheese grater on a standard 16 inch and call it good enough for playing around with various low light optic toys. But for anything practical plain Jane or Mlok seems to be the sensible paths.
Tiny? Bro, every woman on Next Door over 55 has a son with PTSD from operationally operating all over the Bagram chow halls in the GWOT, which is why no one is allowed to use fireworks any more.
Don’t take my word for it, grab a NextDoor account and they’ll tell you all about it, all day for weeks as the 4th gets closer. Then it will ramp up again a few weeks before New Year’s.
Honestly for full disclosure, I have a build like this, which is actually from back then (as in I built it back then, like ’09 or ’10). A2 handle, Troy quad, Magpul XTM rail panels. It’s peak silly but somehow better than the clamshell, at least it’s better as a cudgel. Seemed like a good idea at the time and I did beat the shit out of it back when.
I use it so much these days that I literally am not entirely sure where exactly it is. In the back of one of the safes chillin’ wrapped up for long term storage… where it has been for years. At least I hope that’s where it is.
Maybe I’m just not one for nostalgia.
Must vary by location for vet concentration, know all of 2 within a mile and 14k people for under 55 vets that actually have a deployment ribbon counting myself. Lot of nondeployed vets but is what it is with timing. Now disabled vets……….. leaving that one be but always fun saying g2g with fireworks and I actually did get shot at and had indirect and seeing the autistic screeching of the karens.
The M4 setup does take a lot of abuse but it’s very much a good enough design.
I’m mostly just taking a shot at online Karens (political activists?) here.
I haven’t actually counted, obviously, but given my observations I think this area has a high concentration of women who make shit up because it’s a way for them to take the high ground in an argument which is actually about their own personal opinions on fire works.
The logarithmic increase in such claims since 2020, exactly as the state blued dramatically, supports this hypothesis.
It would not shock me to discover that the whole thing is just an online political activist campaign either, given the dirty tricks the Dems in this state have loved for the past 20 years.
Kinda figured but always pick up new perspectives when I check. Yeah wouldn’t be surprised if there is a reddit (or whatever) for that and a grab bag of other lefty karen issues that has regional breakouts.
It is a fancy two piece replacement for a two piece handguard. Strike makes decent stuff and for those using loose two piece carbine handguards it makes good sense. Best performing old school 12.5″ free float rifle quad rail I have was made in China. Required mods that included using a rare heavy steel barrel nut replacement. With scope, bipod Criterion 20″ .223 Wylde hybrid contour it weighs 10 lbs 13 oz.