Midwest Industries MI-CBUIS Fixed Combat BUIS Review

IWI X95 556 Midwest Industries CBUIS SilencerCo Saker 762
Midwest Industries MI-CBUIS BUIS works great on firearms with otherwise fragile irons, like this IWI X95 Tavor equipped with Saker 762 sound suppressor provided by SilencerShop.

When I first got into modern sporting rifles like the AR-15 in 2004, the backup iron sight (or BUIS) market was very limited. LMT had a set, so did Knights Armorment, and plenty of people simply cut down detachable carry handles. And while all of these worked, more and more companies entered the fray with their own variations.

Midwest Industries MI-CBUIS Fixed Combat BUIS

As development continued these became increasingly complex, and as a result, more expensive. And while I exclusively choose folding BUIS setups for use with magnified optics, for reflex sights, I actually prefer fixed options. But only if they still offer the vast majority of the original optic’s sight picture. In the course of my search for one such BUIS, I came across the Midwest Industries Combat Rifle Rear Fixed Sight (Model #MI-CBUIS).

Midwest Industries Fixed BUIS Close Up
The Midwest Industries CBUIS is milled from billet aluminum but features a skeletonized body to reduce weight.

The Midwest Industries CBUIS is a rock-solid sight milled from T6 6061 billet aluminum. Despite this, the BUIS only weighs 1.98oz according to my digital food scale – so I’ll assume it’s 2oz. While this is almost twice as heavy as Magpul’s polymer BUIS, it’s still impressive for a billet aluminum component. Normally, a sight built from billet would be much heavier, but the engineers at Midwest did a great job with their lightening cuts and partial skeletonization of the base.

The Combat BUIS is adjustable for windage alone. The sight utilizes an M16A1-style adjustment dial that moves the point of impact 0.5 minutes of angle per click. Unlike the A2, this A1-pattern dial requires either a special tool or a single 5.56mm cartridge to adjust. According to MI, they chose this style over an A2 knob because it’s slimmer, and less likely to snag or hang on clothing or equipment while being carried.

Midwest Industries Fixed BUIS Windage Knob
Midwest Industries features an A1-style windage adjustment knob.

Inside the housing, the MI fixed BUIS features a pair of mil-spec aperture “peep” sights. Just like on an M16, there is a larger diameter sight for close range and low light conditions, and a smaller peep or ghost ring for longer range targets. Both work great, but when zeroing your sights, be sure to use the smaller one for added precision.

Midwest Industries BUIS Rear Sight Alignment
To acquire a proper sight picture with aperture style irons simply place the front sight post in the center of the circle. Notice the light distortion from the pinhole camera effect of the rear sight.

One neat effect of peep sights is that they artificially increase a human eye’s depth of field. Permitting us to see not just our front sight post, but also our target with relative clarity. It’s an ingenious design, and one that is still very effective – even if a shooter requires a mild prescription of corrective lenses.

Midwest Industries BUIS Rear Sight Alignment
The peep sight forces a shooter’s eye to focus on the front sight, while also increasing the clarity of the sight picture.

When I first opened the box containing the BUIS, I was actually surprised to see that it lacked an Allen key. But once I turned it over, the lack of a key made total sense. The Midwest Industries fixed BUIS uses a flat head machine screw to secure itself to a Picatinny rail slot. In testing, this holds up fine provided the shooter uses the recommend torque specs of around 30 inch-lbs. If you lack a torque wrench, I’ve found that a rough equivalent to this is to crank down the screw an eighth of a rotation past tight or snug.

Midwest-Industries Fixed BUIS Screwdriver
A shooter only needs a flat head screwdriver to install the Midwest Industries BUIS.

While I primarily recommend shooters use these sights as a standalone aiming device, they do work great with reflex sights. While not a true co-witness, they do provide lower third co-witness, which in my opinion is ideal if the iron sights cannot fold away.

Midwest Industries Fixed BUIS Cowitness Aimpoint
In testing, the MI fixed BUIS works great with Aimpoint optics and perfectly co-witnesses in the lower third of the optic.

Overall, the Midwest Industries fixed combat BUIS makes for a solid, reliable aiming device. They lack some of the creature comforts of more pricey options, but if a shooter needs super-durable irons not made in China for a reasonable price, look no further. MSRP $64.95

PSA PA15 MidLength Midwest BUIS AimPoint Comp M3
The Midwest Industries MI-CBUIS makes a great addition to an entry-level AR like this PSA PA-15 carbine.

About Jim Grant

Jim is a freelance writer, editor, and videographer for dozens of publications who loves anything and everything guns. While partial to modern military firearms and their civilian counterparts, he holds a special place in his heart for the greatest battle implement ever devised and other WW2 rifles. When he’s not reviewing guns or shooting for fun and competition, Jim can be found hiking and hunting with his wife Kimberly, and their dog Peanut in the South Carolina low country.

Jim Grant

Notify of
Most Voted
Newest Oldest
Inline Feedbacks
View all comments

That torque is INCH pounds, not foot pounds.




Omg! It’s that gun in the streets I’ve been hearing so much about! I’ve never seen it before!