Category Archives: Reviews

Review: Midwest Industries SS7 free float tube

Now that I’ve finally finished my lightweight AR-15, I’d like to write a review of the Midwest Industries SS7 free float tube that I replaced the handguards with.

I’m going to be occasionally comparing the SS7 to the YHM Customizable Free Float System, which was my first choice before I discovered the SS7. I have nothing at all against YHM or their products, but I hope to demonstrate how the SS7 is superior to the YHM tube.

I got my SS7 from MidwayUSA for about $130. Since then, AR-15tactical has been selling them for $119, which is just ridiculous. Seriously, go get one. By contrast, the YHM tube can be found for as low as $100 at Area 51 Tactical, which is also a ludicrous steal.

First, here’s what it looks like on my AR:


I stupidly forgot to take a picture of just the tube before I attached it, so here’s a generic marketing picture:


Now for the details:


This thing is light. Really light. Unattached, it feels like it’s practically not even there, which I think is mostly a function of its size given its mass; you expect it to weigh substantially more when you pick it up. In total, the whole shebang weighs 7.8 ounces without any additional rails segments attached, which is actually less than even the lightest single-shielded carbine handguards (including the factory barrel nut, delta ring, and handguard cap, of course). Remember, this isn’t a smooth carbon fiber tube or anything; it’s an honest-to-god aluminum free float tube with picatinny rails and everything. I am just absolutely astonished by the weight. By contrast, the YHM tube is 9.5 ounces with no rails at all, not even the permanent top rail that the SS7 includes. That’s heavier than the heaviest M4 handguards, which weight 9.3 ounces.

The weight savings is mostly achieved by perforating the tube with big ol’ holes, which are also used to attach the included accessory rails and are spaced 45 degrees apart around the tube. There are six holes at the 3, 6, and 9 o’clock positions, and seven at the 1:30, 4:30, 7:30, and 10:30 positions. I find the pattern to be very attractive, and the openness of the tube allows heat to dissipate very quickly — and right into your hand! In practice, it’s not going to be a problem as long as you’re not dumping multiple magazines in a matter of seconds.

Fit & finish

I have to say, the SS7 is a very handsome-looking free-float tube. I really like the clean design and the fact that the built-in top rail extends a little beyond the jam nut so it can touch the rail on the upper receiver for that “monolithic” look. I don’t plan to mount anything on it, and I would probably appreciate it being removable to shave off another few tenths of an ounce, but I have to admit that it looks very attractive. No biggie.

One thing I would prefer is if the tube were teflon-coated, like the Spike’s Tactical lower receiver that the gun is built upon. The SS7 feels noticeably gritty and metallic, not at all like the silky smoothness of the receiver. This is purely cosmetic and obviously not a big deal, but it would be nice. It really made me appreciate the Spike’s Tactical product even more, though.


Installation is pretty standard and matches the procedure for YHM tubes; with the right tools, it’s not a big deal. In fact, both tubes appear to use the same barrel nut and jam nut. Unlike the YHM tube, though, the SS7 incorporates an anti-rotation screw.

But it looks like Midwest industries has taken the jam nut and drilled shallow holes in it so that it can interface with their proprietary tool. This seems a bit unnecessary, since it already had slits that worked perfectly fine:


A happy side effect of this is that you can tighten the nut with YHM’s tool or any of the newer AR-15 armorer’s tools that include free float wrenches to tighten the nut. My armorer’s tool does not include this, so I bought Midwest Industries’ proprietary wrench and it works fine. I probably could have banged on it with a hammer and a flathead screwdriver if I was desperate enough.

Once mounted, the tube feels absolutely rock solid. There’s no play or flex at all, which is of course what you should expect for any decent free float tube, and the SS7 is no exception. It also feels very nice in the hand due to its round shape. I specifically wanted to avoid quad rails that need rail panels all over them to be comfortable. The holes in the tube give it a slightly grippy texture, too. As you can see, the tube’s top rail lines up perfectly with the one on the upper receiver:


Accessory rails

The included accessory rails mount easily enough and they can go right where you want them, even in weird places like the 11:30 position — anywhere there are holes. I didn’t have anything to mount to the rails, so I haven’t made use of them yet.

Just by looking at them, though, I can tell that they’re quite thick and chunky, extending about 3/8″ from the tube. By contrast, YHM offers lower-profile attachable rails that are only 1/4″ high, although to be fair, the small one that comes with the YHM tube is as high as the ones that come with the SS7 so you’d have buy it separately. But buy it separately you can, whereas the same can’t be said of the rails offered by Midwest Industries. You’re stuck with fatty rails.

Sling mount

I opted to attach my sling (the excellent Viking Tactics two-point adjustable sling) to the tube via the Midwest Industries SS-SA sling adapter. Like the rails, it’s a fairly chunky piece of hardware, and it requires three holes worth of space on the tube to attach. Although the whole thing isn’t very heavy (1.5 ounces, including the sling loop itself), it is bigger than I would prefer.

In trying to find a good place to put this thing, I ran into a problem: there weren’t enough holes in the tube where I wanted them. I really wanted the mount to be as close to the upper receiver as possible, but the closest hole was 2 inches in. Due to the length of the mount, this meant that the sling loop itself would be about 3 inches from the receiver—almost in the middle of the 7-inch tube!

I ended up mounting it like this:


Even though it’s only attached to the tube with one screw, it still feels rock solid due to the interior curvature of the mount hugging the exterior curvature of the tube. This seems sort of like a hack, though, and I’m sure the sling mount could be better designed to more efficiently make use of available space.

One final gripe is that the QD sling loop itself feels low-quality. The gritty finish is already coming off the loop itself, and covers my fingers in black stuff whenever I handle it. By contrast, the QD loop I bought from UTG feels much nicer and smoother (yes, I’ll be a man and actually admit that I bought a UTG part). I know that looks aren’t everything, but the UTG one has ’em, and it doesn’t seem to function any worse for it.


Midwest Industries QD sling loop at left; UTG one at right


Despite minor quibbles, I heartily recommend the Midwest Industries SS7. If you’re currently looking at the YHM Customizable Free Float System, going with the SS7 is a no-brainer unless you absolutely hate the built-in top rail or the holes. I mean, the cost difference is less than a few pizzas, and the SS7 is almost two ounces lighter, which is a big deal. Here’s the breakdown of advantages for each product:

Midwest Industries SS7:

  • 1.7 ounces lighter
  • Anti-rotation screw
  • Built in top rail

YHM Customizable Free Float System:

  • A bit cheaper
  • Can buy lower-profile attachable rails

I think there’s no contest. YHM could put themselves back in the running by shaving an ounce or two off their tube. As is however, you owe it to yourself to pony up the extra $20 and get the lighter SS7 rail. You’ll love it.