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Saturday, September 24, 2016

MFT Polymer Backup Sights

If you have been reading the blog for a while, you'll know that we're a big fan of Mission First Tactical and the gear they make.  So we were very excited when they announced that they were releasing a set of back-up sights.



What They Are

MFT 's back-up sights, the BUPSWF (Back Up Polymer Sights With elevation Front) and the BUPSWR (Back Up Polymer Sight Windage adjustment Rear) are lightweight, low profile folding sights designed to be as light and low profile as possible.  This has led to some interesting design decisions that we will discuss later.

Mounting the sights is relatively easy.  You remove the crossbolt from the sight and place the red plastic shim in the desired rail section with the open end of the U facing up.  Place the sight on the rail channel and thread the bolt back in, being careful not to over-tighten as it is very easy to cause the nut to strip out the pocket it sits in.

The sights are shrouded and protected from damage when folded, the tower of the sight forms half of the cover, the other half is retracted to allow the spring-loaded sight to flip up into position. The sights are held in place positively by spring tension, but they do not lock into place.  This allows them to fold up if struck or the rifle is dropped.



The rear sight features a windage-adjustable aperture sight, with both large and small apertures.  The sight can be folded with either the large or small aperture up.  Adjustment of the rear sight is accomplished by turning a flat-head screw on the right side of the sight.

The front sight features an elevation-adjustable front post, which adjusts with a standard front sight tool.  It's the standard mil-spec dimensions, and can be swapped for any standard front sight post on the market.  Like the rear, it is spring loaded, and shields itself when folded, and is held in place by positive spring tension.

The sights are incredibly lightweight, weighing just .5oz per sight.  The Magpul MBUS sights by comparison weigh 1.3oz for the rear, and 1.2oz for the front.  If you're looking to shave weight off your gun, consider that you can mount both MFT sights for less than the weight of the Magpul sights.


Shots Fired

So, what do I think of them after testing them for several months?  I'll give you the short version if you're in a hurry.  I don't like them, and I can't wait to take them off my guns.

Why?  When installing them, the cross bolt that attaches them to the rail easily strips out the nut on the other side, which is just bedded into the plastic sight body itself.  The nut is too small and the polymer is too soft, and it just ends up spinning and is a pain to tighten or loosen.  I tend to over-tighten things like my sights, which I need on my gun.  This will strip the nut immediately.

But it gets worse when you go and fire the gun.  They zero just fine, but I have had three sets of them pop open under the firing impulse of the AR-15's they were tested on.  We have one rear sight that has not done this, but the other three sets will pop up in less than a magazine's worth of fire.  If you are running optics and a set of sights pops up unexpectedly in your field of view, it's not a good thing.

If you were thinking of running these sights on a .22 rifle or an airsoft gun, you may have better luck.  But even if you are using these as your primary iron sights, there's another hitch.  There's a small cross pin on the rear of the sight cover, which holds the retractable cover to the sight body.  These pins tend to walk out under fire.  I kid you not.



What really set me off is that if lubricants get into the sight, all these problems are exacerbated. The pins walk out faster, and the sights pop up quicker as everything is held together by friction.  Do you take your sights off before you clean your rifle?  If you do, you're the first person I've met that does. So expect to get some CLP in the works, and that's going to make life that much harder.

It's like Clippy is on your rifle, popping up all the time.  "It looks like you're trying to aim?  Would you like a sight?"



Personally, I like MFT's stuff, and I always have.  I'm not slamming that company, most of my rifles look like MFT ads, and I'm ok with that, because I like their gear.  But this is just a bad product from a company that usually brings its A-game.  The Minimalist stock is a perfect example of that.

Personally, if I were to make these sights, I would focus less on the weight and more on the durability.  It's easy to stay under the weight of the MBUS with the current design.  Use a more robust mounting screw, ditch the rail shim, and use a larger nut to prevent stripping of the attachment screw.  Use roll pins or hex pins to stop the pins from walking out, or use captured pins or a c-clamp like AR-15's dust cover.  Use an actual locking mechanism or a high-friction mechanism to stop the sights from popping up.

If MFT does that, they will have a solid sight on their hands, while still reducing the weight of the system.  They are accurate and adjust easily enough with the tool in your range bag. The actual sighting mechanisms are as good as any mil-spec sight on the market, they just need to be beefed up before they are ready for the big show.    

If they can fix the stripping, walking, and popping issues (yes, I'm pretty sure that's a rap song), then these might get another go, and I really hope MFT will, because these sights had a lot of promise, but were underwhelming in the execution.

You can head over to MFT's website to check them out here.

Don't forget to head over to KCT Kydex and gear up!