Ultradyne Back-Up Iron Sights
The new Ultradyne back-up iron sights for the AR-15 are the most innovative back-up iron sights that I’ve used; particularly their HK style front sight. Unlike the fundamentally flawed HK style front sights manufactured by Troy Industries, Precision Reflex, Samson etc, the Ultradyne HK style front sight maintains the proper orientation of the front sight post within the circular front sight “ears” throughout its entire range of elevation and windage adjustment. The entire sight housing moves when making adjustments.
You may have noticed in the previous sentence that I said “elevation and windage adjustment.” The unique feature of the front sight having windage adjustment allows you to obtain a no-wind zero by making adjustments solely to the front sight.
The Ultradyne front sight employs interchangeable front sight posts. There are currently five different front sight posts available; four of them are aperture posts and one is a square post the size of the standard A2 front sight post. The interchangeable front sight posts are a proprietary design. Mil-spec front sight posts will not work with the Ultradyne front sight.
The Ultradyne rear back-up iron sight also has interchangeable apertures. Two rear apertures are currently available; a 0.050” aperture and a 0.070” aperture. The rear sight can also be used without either rear aperture installed, giving you a ghost-ring sight picture. The rear sight is also adjustable for windage and elevation.
I mounted the Ultradyne back-up iron sights (with the 14 MOA aperture front sight post and 0.050" rear sight aperture) on one of my Krieger barreld AR-15s. Using match-grade hand-loads and shooting off-the-bench at a distance of 100 yards, I was able to achieve a 10-shot group that had an extreme spread of 0.71”.