A Test of Rifle, Caliber .223, AR-15 – From 1960
Aberdeen Proving Grounds 1960 AR-15 Test
Linked above is a PDF report from February, 1960, about some early AR-15 testing. I've had it for a while but don't believe that I've discussed or posted it in the past. There's a large amount of technical data, to include precise gas port diameter and location, distance the bolt travels before unlocking, precise travel of the front sight post per notch moved, and so on.
It also includes multiple 10 shot group accuracy testing, 6000 round endurance testing, extreme heat and cold testing, dust testing (though limited in scope), mud testing - which appears to be far more involved than the "mud testing" we see on YouTube from time to time, as they introduced mud to the FCG, causing failures of the trigger to return forward on its own - something I have encountered while trying this as well - rain testing, and cook-off testing.
Broken parts were encountered, and as described in the appendices, they included extractors, extractor springs, and firing pins, but also rather nonessential parts such as a trigger that broke in the -65F testing but was not replaced because the weapon still functioned, handguards that came unriveted, cracked stocks, sling swivels that came apart, etc.
It should be noted that these weapons were functioning at a cyclic rate of between 746 and 796 rounds per minute. Many variants of the platform available today operate at much higher rates of fire, to their eventual detriment.
A.R.M.S. #71 Sights – Video Review
I had intended to make a longer review, but I'm unable to do voiceovers at the moment, so I'm just going to go with an "at the range" overview that I filmed last weekend.
In my opinion, these sights are less than functional, and the reasons why both the front and rear sights have major problems are very obvious.
The front sight's release latch doesn't always return to the "forward and upright" position, meaning that some of the time you want to fold the sight down, you have to physically move the latch into place. Sometimes it does. Consistency, even if it was in a less than desirable manner, would be nice.
The rear sight is designed to allow both the large and small apertures to lay flat on top of one another, leaving a lot of room for optics. Unfortunately, when the rear sight is sprung upwards into place, the small aperture moves forward at roughly a 45 degree angle, blocking the shooter's view of the front sight almost completely. The only true solution to have the rear sight ready to use the instant it's moved up into place is to leave the small aperture folded away from the large one, reducing scope clearance and not allowing the user to immediately use the small aperture if he so desires.
In the video I describe the sights as "absolutely useless". Perhaps this was going a bit too far, but I do not find them to be very functional as-is. Initially, they looked nice, and I liked the low profile of the rear sight - but as I actually used them, I found that I would...never want to actually use them on any of my rifles. If I wanted to use polymer sights, I would buy the Magpul MBUS, which are better designed, and as a result, they work as intended.
I'm reviewing them separately from the NGA X7 (which came equipped with them) because they were an optional accessory, and I didn't feel that their poor performance should reflect upon the rifle.