It sounds and looks normal to me.
100% normal / within spec. Welcome to the A2 / A3 sighting system.
When the M16 Product Improvement Program of the early 1980’s was cranking up The Army pretty much gave the Marine Corps a free hand in most of the details. The Marine Corps pretty much handed it to the competition gurus at Quantico. There are a few things which ended up in the final M-16 A2 configuration that can lead to some “head scratching” when viewed through a gun-fighters eye. When viewed through the eye of a service rifle competition shooter things make slightly more sense. But like the man said “… We ain’t going to Wyoming to shoot canteens boy…”
Bottom line the A2 sights work VERY well for the service rifle precision critera of that era. Canted rear base and all. If they hadn’t The boys at MTU Quantico would have had changes made quicker then a jack rabbit gets a date.
Back in the day Armalite was offering a “National Match” base which had a spring and detent on both the right and left sides. It was a decent product that worked well - got rid of the cant for us OCD types - which as previously pointed out is from spring tension on just one side. If memory serves they only offered this for the A2, and not the detachable handle
But wouldn’t that at least marginally improve accuracy?
(New guy here who just got a mil-spec PSA carry handle sight for a PSA M4 build, and I thought something was wrong with the sight. Joined the Forum to bring up that very question and then spotted this thread.)
Yes.
Pinning is how places like CLE do it currently (and for a good many years now). They are not shimming or using 2 detents as the other guy mentioned.
The thought of shimming was intuitive to me as I would see a gap open on the right when I would mash the platform back that way; I have a gap gauge and found a range of thickness that would keep the gap from closing completely and hold everything in line.
What exactly is pinning? Putting a little “door stop” in there somewhere to inhibit the leftward movement of the right side of the platform?
And finally, does CLE refer to Compass Lake Engineering?
Why anyone would shim or whatever is curious. The sight pivots on the center of the apperture, so shimming doesn’t accomplish anything.
I know the Camp Perry type shooters have more precise sight rigs, but for non-competition shooting, there’s no need to modify an “in-spec” sight system.
I did have a piece of shit bushmaster where the rear sight would track off to the right as it dialed up. I refused to accept it for a long time until I set up paper at 50 or 100 and watched the bullet holes drift up and right as I dialed the sight up.
We’re in an ARFCOM wormhole back to like 2005. I think most people new to the A2/A4 sight look it over with some curiosity.
But now, most shooters have an RDS or some sight, and never shoot iron field sights… let alone dial for distance. It’s fun marksmanship shooting and stretches your rifle reach.
Wouldn’t it allow you to sight through a circle instead of an ellipse?
The center of an oval (if you can even tell while firing) is the same as the center of a circle. I’ve fired out to 500yds on known distance ranges and approx 500yds on unknown distance and it didn’t make a practical difference. The rack grade rifle still made hits to the capability of the ammo. To reliably produce a basketball size group on target at those ranges is obtained by properly dialing windage and elevation combined with basic fundamentals.
The app simply does not can’t that much.
But you get more light through the circle, and the light is more equidistantly distributed around the tip of the sight post. And my poor old eyes need all the light they can get.
My eyes too. But the can’t is negligible. At least on my guns.
I really don’t think that if I were on the gun and I reached up and turned the sight that I could tell the difference.
Are you okay?
That’s a standard A2 / A4 rear sight.
There were two ways to fix it for those with Obsessive-Compulsive Disorder, or National Match shooters.
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Weld a small “Tit” on the right side of the housing and file it down to ensure the housing is exactly parallel with the handle’s U-notch, or
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Have a machinist drill straight down the observation hole in the top of the sight and insert a pin to ensure the sight has no left-right movement. This one is double-pinned:
These practices have pretty much “Gone away” now that National Match shooters use 4.5-power telescopes.
Why does that drum have a 0 on it
Isn’t the National match drum marked in number of clicks, starting at zero?
So my guess is it’s a NM drum
Since we’re talking here about the line of sight passing through the center of the circle/oval, I’d like to ask a peripheral question about the line of sight in relation to a mil-spec carry handle: What exactly is the vertical distance between the center of the long-distance aperture and the bore axis at mechanical zero? I’ve come across “about 2.5 inches” and “about 2.6 inches.” Shouldn’t there be a little more precision here?
Yes. Some sort of competition sight. You can tell by the app in the base… Now with that App, you might not want any sight base cant due to it’s length.
Yes, I was talking about Compass Lake earlier.
All of my hooded rear sight bases from them have interchangeable apertures. You can fine tune exactly how much light you want coming through. And no, they don’t have to be ‘pinned’ to be hooded like that and still work well.
With the exception of Sinister - You got lots of guys posting here that have no hands on experience with these. It is fairly obvious from the comments.
I don’t know what CLE does these days but back in the early 2000s White Oak Armament was the place to go if you wanted rear sights pinned. I recall it being common knowledge back then that this was purely an OCD type thing. Many high master class shooters had uppers with and without pinned sights and they were definitely not considered a mandatory addition.
However if having such things perfect and square improves your outlook on your equipment and your performance and you have the scratch to spend doing it …and youre sure the money wouldnt be better spent on ammunition/practice, then I’d get it done. They can definitely inspire confidence.