This week we finally got our hands on the Ultradyne Mercury / C4 Dynamount Sight Combo. Due to it's late arrival, we'll do an intro here and follow-up with a more detailed review once we get a chance to really work with it.

Ultradyne USA is a relative newcomer to the AR world, but they have an innovative products that are sure to be a major success.

The product line currently consists of backup iron sights and muzzle devices. I hesitate to call them "backup" iron sights because even though they are designed as such, with the ability to fold out of the way of a primary optic, they are far more functional and accurate than any iron sights the AR platform has had in the past.



We'll do a quick overview of the product line here, as there are many options and combinations available.

First of all, all of these are 100% CNC steel and aluminum machined in the US, and are IMHO the best engineered and built iron sights available for the AR platform. They are full of well thought out and innovative features that set a new standard for iron sights.

C4 Precision Folding Rear Sight
The rear sight is a feature-rich, low profile folding design that includes a number of well thought out features, designed to work with the C4 front sights. It mounts to a standard Picatinny rail, is machined from CrMo steel (nitride finish) and 7075 Aluminum (hard anodized), and weighs in at 2.5oz. ($154 MSRP)



Like the matching front sights, they are able to be deployed and stowed with a single hand simply by pulling up or pushing down to raise and lower and latching securely in either position. There are no locks or buttons to press. All adjustments are tool-less.

It uses an interchangeable aperture so you can go anywhere from a threaded ghost ring (with no aperture installed) to a .070" (included, and equivalent to the small A2 sight aperture) or the smaller .050" target aperture. If you remove the included or have an extra aperture, it threads onto the elevation adjustment knob so you can keep it on the sight.

Windage (40MOA, 1/2 MOA per click) and Elevation (18MOA, 50 yard BDC clicks to 600yds) are available on the rear sight. Because the front sight ALSO features windage and elevation adjustments, your zero can be done using the front sight, leaving rear adjustments for particular shooting conditions.

C4 Precision Folding Front Sight
As we just mentioned, one of the most unique features is that the front sight has both windage (40MOA, 1/2MOA per click) and elevation (28MOA, 1-1/4MOA per 1/4 turn) adjustments. This allows you to zero using your front sight only, leaving center-zero operation of your rear sight with full range of adjustment. Adjustments are very simple, and can be done without the use of tools. To adjust elevation, you simply press down on the body of the front sight, and turn the center post. Releasing the body raises it to lock into position, and maintain the front sight pin centered in the protective wings.



Another unique feature is that rather than a traditional solid post (which is also available), the front sight features a post that is drilled out on all four sides so you actually center it in your rear-aperture, and then center that on your target by looking through the center of the front sight post. As they describe it:

Most BUIS systems utilize a sight picture that is non-intuitive. The brain’s visual systems are asked to align a circular rear aperture with a rectangular front post shape while simultaneously ignoring the “ears” that protect the front sight post. Dynalign’s circle-within-circle sight picture allows for faster sight picture acquisition. Additionally, the use of a front aperture further reduces parallax effect which makes accuracy less dependent on precise sight alignment.



It is easy to use, and certainly makes sense to be a much more accurate solution. Front sight posts are interchangeable and available in various sizes including 8MOA, 10MOA, 12MOA (standard), 14MOA, and an A2 blade. These allow fit to be adjusted for your sight radius and target needs.



There are two options available for mounting: a standard Picatinny, and a Dynamount. The latter allows the front sight to be mounted using their proprietary barrel mount which provides flex-free sighting when pressure is applied to your hand-guard inducing flex.

Front sight weight is 2.2oz for both mounts, and it is machined from CrMo steel (nitride finish) and 7075 aluminum (hard anodized). ($129-$155 MSRP)

Muzzle Devices
There are a number of muzzle devices available, and in order of increasing cost, they include: Athena ($47), Mercury ($89), Apollo ($99), and Pegasus ($99). There are versions for .223/5.56 and .308/7.62, and front sights must match your caliber choice. Ultradyne offers combos which include a front sight, muzzle device, and option for a rear sight.

Each of these come with a timing nut, and a muzzle device collar. The latter is used if you are not using a Dynamount front sight, so it's basically a spacer that fills the gap where the front sight would mount.

We will be testing the Mercury which they describe as follows:

MERCURY has been meticulously engineered for the .223 | 5.56 caliber to provide superior recoil reduction and neutralize muzzle rise with a smooth, balanced release of blast energy. Progressive 90º side ports vent combusting gases at intervals that spread out the recoil impulse for efficient, accurate follow-up shots.



Ultradyne's full line of muzzle brakes/compensators were designed to combine shooting comfort and performance at different levels to accommodate each shooters preference.



Ultradyne products can be purchased at Brownells. Videos are also available from Brownells on the C4 sights and the compensators:




I'll update this thread with photos and then video once that's available, including a range report. Feel free to ask questions or post your experience here.

There are three holes in the muzzle device, and a "pin" on the sight base. These allow you to index it at 90 degrees or 45 degrees to either side (but no provisions from Ultradyne at this point for rear sight to be mounted at 45 degrees, so you have to choose a third party solution for that I guess), and so the muzzle brake and sight are indexed together. Then the nut behind the sight base screws forward to hold everything tightly together.



So the order of assembly is to put the locking nut on the barrel, and thread it all the way down (it is countersunk so the barrel will recess into it). Then you put the front sight on with the pin facing forward. Then you thread the muzzle device as far as you can get it to go, so that when indexed with the front sight base, they are both aligned and pointing straight up and could not make a not the full rotation. Last step is to tighten the locking nut forward against the sight base, holding everything together.

Remember the whole point of free floating the barrel was to avoid pressure on the hand guard from affecting the barrel by not having the two touch. The same thing with the front sight; if pressure is put on the hand guard, the front sight mounted on it would flex and move independent of the barrel throwing off your accuracy. This keeps the two parts that need to be consistent for accuracy (the barrel and the sight) together, and not affected by the hand guard. This is especially true with the tendency towards longer hand guards these days.

Also remember these are 'precision' sights meant for longer range work, not necessarily for the short pistol upper I have them on in the photos. In addition to everything else, they maximize your sight radius by putting the front sight as far forward as possible; literally at the end of your barrel.

Unfortunately I have no insight beyond their current product line. But I’m guessing making suggestions and requests directly to them would not hurt anything. The goal I think would be to make a muzzle break that also effectively reduced muzzle flash, which these may or may not already do to some extent. If I had the full product line, I would perform that test...