5.56 Timeline

Optic of the Week: CSAT Folding Rear Sight

I think we are in the end of the age of iron sights. Not that they are going to suddenly go away, but more and more individuals and groups will feed no need or desire to use them in place of optics.

My dad bought a CSAT folding rear sight, and told me it didn’t work well for him. I was surprised he bought it since I was sure he perfectly happy with the ACOG/Mini Red Dot combo. I had a CSAT aperture years ago, and I liked the idea of it, but decided I’d rather put the money towards something else.

The CSAT sight was designed by Paul Howe and the intent is to have a peep sight for use at 100 yards, and a notch above for 0-7 yards.

I can’t find when I purchased the CSAT aperture I had. I think it was installed in a LMT rear sight. I did find an old note from 2009 saying that I wanted to get one, so it must have been after that. I remember shooting with it, then decided I liked the Knights Armament 2-600m rear sight better.

I didn’t know that XS Sights now makes a their own flip up rear sight. The design is similar to the Troy flip up sights, but it doesn’t look or feel as refined. It locks in the up position, and you need to press the button on the left side to lower it. The windage is easily adjustable with the knob on the right side.

I went ahead and threw the sight on one of my uppers, and gave it a try.

My dad said that when he would look though the CSAT sight, the thin bit of material between the peep and the notch would appear to disappear and it would become a giant U notch. I didn’t remember having this happen before when I had a CSAT aperture, but sure enough when I tried aiming at a wall in my home it happened to me every time.

Good in theory, but the aperture ring ghosts out & can’t be seen. It leaves you w/ a giant deep U sight picture. Not worth the cost.

Review from Midway USA.

Indoors, nose to the charging handle, this happened to me 100% of the time. If I backed my head away from the sight it became usable. Outdoors in sunlight I rarely had this issue. But it happened enough that I would never buy this sight.

The XS CSAT aperture is like an A2 aperture, but same plane. So there is a large opening and a peep that share the same zero. On this flip up sight, when you flip it up it will have the large aperture up.

If you want to use the CSAT aperture, you have to flip up the rear sight, then flip the aperture. That doesn’t make sense to me. They should have had it default to the peep+notch.

It has probably been nearly a decade since the last time I used the CSAT sight. I was dismayed to find that the notch felt HUGE. I wasn’t centering the front sight post in the notch, I was centering the entire front sight. That felt slow to me.

I had remember the CSAT as being a good sight that wasn’t for me. Using it now I thought it felt terrible. Like the notch had been made to large and interfered with the use of the peep.

When I was going to test this, I thought I would do a rough and hasty 300m zero, by zeroing a half inch low at 25 yards. Then I was going to shoot at 7 yards. I was shooting a couple of rifles, and in my haste I fired on a target I had already used. I had a really hard time trying to shoot that 3 shot group for zeroing. I couldn’t get focused on the front sight and the 3/4 inch red dot I was aiming at disappeared. The group I shot was awful.

3 shots fired with an Aimpoint PRO, note they are close together. The 3 shots with the CSAT peep were about a 2 inch group at 25 yards.

Now, normally I would say that I was shooting poorly. But I had just fired this other group with the same ammo, same distance, out of the same type of barrel using a KAC 2-600m rear sight.

3 shots, M855, 25 yards, using a 6945 and a KAC 2-600m rear sight.

The groups were shot about 5 minutes apart from each other. Shooting with the KAC sight felt easy, I was really struggling with the CSAT sight peep. After seeing how bad the group was, I made no adjustments. So I decided I wasn’t going to try and fine zero, I would instead try some faster shooting up close.

I set up up more of these dots at about 7 yards. (Thank again to the nice guy who gave me oh too very many of these red targets after he had a ton of them made for himself.)

To show the purpose of the notch, I fired some fast shots using the peep aperture of the CSAT.

Aiming directly at the red dot, I fired 5 shots of M855. You can see how the point of impact is much lower than the point of aim. The idea of the CSAT notch is so in close range situations when you need to make a precision shot, you can.

The value of the notch is being able to aim right as what you want to hit up close.

I had a handful of wolf ammo laying around, that I wanted to use up so I used it for this group. Maybe 12 or so rounds. I should have paid closer attention. The target was engaged with single shots at a moderately fast speed. Lowering the weapon between each shot. I felt really slow, as it seemed liked the whole front sight base was visible in the that notch and and I had to find the front sight post in there and line it up with the top the rear sight notch and center everything.

That would be a training and familiarity issue. More practice with the sight would lead to faster target acquisition.

If you had asked me about the CSAT aperture before last week, I would have told you it is a nice product, but something unneeded, and that something like an Aimpoint would be a far better choice on a modern fighting rifle. I wonder if they changed the design since then.

Now, having used the CSAT sight again on XS folding sight; I feel like XS flip up sight body is ok, but crude compared to others. The CSAT aperture felt terrible in use for me. I would rather use a standard A2 or detachable carry handle over it. I think I would rather use just about anything else over it.

Optic Of The Week : NightForce NXS 5.5-22X56mm

NightForce optics need no introduction or explanation, everyone above 5 years old knows who they are and how good they are. So lets get to it.

The NXS is a pretty big optic. But you get a lot for that size. Now its no doubt considered old and past its prime compared to new designs coming out nearly ever month, it’s still first class in my opinion.

Magnification:5.5 – 22 x
Tube Diameter:30 mm
Reticle Focal Plane:Second Focal Plane (SFP)
Illumination Color:Red
Eye Relief:3.9 in
Exit pupil:2.5 – 10.2 mm
Adjustment Type:MOA
Adjustment Range:100 MOA
Field of View, Linear:4.7 – 17.5 ft at 100 yds
Length:15.2 in
Weight:32 oz

AS the specs from NF say above, the NXS turrets adjust in 1/4 MOA clicks. I know its “obsolete ” to use MOA instead of Mils now a days but I like it. I been using 1/4 adjustments for 30 years, I am comfortable with it, I know it and it works very well for me. The turrets can be loosened and reset at zero like most modern tactical scopes.

The left side parallax knob also functions as the illumination control for the reticle. You pull out to turn it on and push it back in to turn it off. The cross hairs light up red but are not day time brought. There is no brightness control though it can be done, I wouldn’t really mess with it with out much care.

The reticle is the now discontinued NP-R1 reticle. ” 1 MOA elevation spacing and 2 MOA windage spacing are ideal for precision long range shooting, benchrest and all-around use. The fine reticle subtensions are effective for rangefinding objects of various sizes. NP-R1 reticles in Nightforce 5.5-22x, 8-32x and 12-42x NXS models show 20 MOA scale below centerline (at left). In the 3.5-15x, an additional 10 MOA scale below center is indicated on the reticle. “ I find it to be very useful and it’s just what I wanted for what I use the optic for. Not as sexy as current Xmas tree crosshairs but perfect for me.

The rear power ring is knurled for easier gripping. The entire rear turns with the power ring to make it even easier. That is the one thing I would change if I could. I rather the power ring turn and nothing else. But I got over it pretty quick.

I can’t recommend the NXS enough. Howard can tell you, I wanted one for years. I have not be disappointed. They are tough, repeatable, super clear glass and come in a variety of reticle choices. They can take a helluva lot of punishment and shrug it off. As much of a Leupold man as I am, I hold NF in the same regard. it is a bit of a more specialized optic though, so make sure you know what you are going to use it for, It’s not something you stick on an M4 for general do it all use.

Optic of the week: Trijicon TA31I Israeli issue

I came across something I had to pick up. Fortunately I’ve been selling off odds and ends I don’t use so I had a few extra bucks.

At first glance, it looks like any other 4x magnification dual illuminated ACOG.

But the markings are a little different.

I’n the past I’ve seen pictures of the Israelis using TA01NSN ACOGs that have a crosshair with bullet drop chart (BDC). Later pictures show a dual illuminated model. I had just figured they were using TA31F scopes or similar. Turns out they custom ordered a model. It has markings specific to them and a custom reticle.

After getting one of these surpluses scopes, I installed some adjustment caps and a mount that I had laying around. I suppose it helps that I am an ACOG junkie. I threw it on one of my rifles Saturday for test firing.

Adjustments appear to be the standard internal 1/3 MOA. Operation is just like any other older 4x ACOG.

The reticle is a dual illuminated donut. There is a BDC out to 500 (meters I would wager), and horizontal lines. I find these lines quickly draw the eye to center of the scope, and I think this reticle would be rather fast for quick shooting.

I have yet to be able to get a copy of the manual for this model, so I don’t know what the markings and subtensions are. I’ll update this post when I find out.

The Tritium is completely dead on these surplus optics. I wonder if it was removed before they were brought into the US to aid in importation. I imagine it was probably quicker and easier, maybe cheaper, to replace the optics verses having them rebuilt, so that is why these likely have been surplussed out.

Optic of the Week: 1P29 Tulip

1P29 Tulip, AKA UPO-1 is a Soviet era 4x scope based off the Trilux/SUIT scope.

TexasZen has a great write up on them over on his site RussianOptics.net. Here is the 1P29 page.

But who cares about his opinion, here is mine:

I had been wanting to get a scope for my 5.56×45 SLR-106FR AK for a while. Wasn’t sure what I wanted to get, but this was one of the optics I was thinking of. When I went to order the PERST-4 Laser from IvanTactical, I decided to order this as well. It came straight from Russian in 7 days.

The scope came nicely boxed and in a canvas? gear bag.
The scope came wrapped up to protect it (partially unwrapped in these photos). It also came with a manual, adjustment tool, lens cloth and some caps.

The 1P27, sometimes called the UPO-1 for the commercial market slides right on to your rifles side rail and locks on. AK side rail scope mounts tend to be looked down upon by western shooters, but it is a simple system that just works. Although, it can make optics bulky.

My first thought about the scope is that it seemed a good bit larger and bulkier than I expected. But it is older tech. If you are really wanting the best fighting optic for an AK, you should be buying a newer western optic.

An inverted post provides the aiming point in the 1P29. Tritium illuminates the tip during low light conditions. The tritium in mine is rather dim. Some people have figured a way to replace the tritium in these optics. If you buy one of these optics, don’t expect the tritium to be bright enough to be useful. I had forgotten that these were illuminated, so I was surprised when I saw it glow dimly in the dark.

On the right side, there range finding reticle based off a 1.5 meter height. This is kind of odd as most of that style that I know of use a 1.7 meter height. On average, males tend to be between 1.6 and 1.8 meters tall. Hmm, maybe these were calibrated for shooting women? Might be for vehicles, but still an odd choice for height. Some hunting calibrated range finders use a 1 meter height. So many of the classes I took in the Corps tried to teach us to range find the enemy off the height of a Humvee, and I always asked why the enemy had Humvees and the instructors wouldn’t answer me. So I dunno.

The optic is clear, but has some noticeable fish eye effect. This seems pretty common in Russian optics.

The scope sits high enough to easily use the iron sights under it. The eye piece is centered over the rifle, but the objective lens is offset to the left.

There is a cam, with knobs on each side of the optic ranging from 400-1000 meters in 100 meter increments. In the picture above it is set to the 1000m setting. When I took it out of the bag, this adjustment was extremely stiff. After turning it a few times, it can be adjusted stiffly. No concern of it accidentally being turned. The cams are calibrated for 5.45×39 or 7.62x54R.

We tend to take for granted the idea of center of mass being the center of chest. I’ve seen something when you tell someone center of mass, they assume a point closer to the belt line. The Russians like to do something similar. They use a 400m battle sight zero so that an individual can aim at the targets belt line and know that they will hit the torso anywhere from 0-400m. The people I’ve told this too in person seem to find it odd, but it isn’t really that dissimilar to our militaries 300m zero. If I’m not mistaken, the AK74 400m zero puts the impact about 9 inches high at 100m, and 14 inches high at max ordnance.

I am using a 5.56, so my intent is to zero at 100 yards and hold over for other distances. But I started at 25 yards.

Windage is adjusted by a screw on the right side. CCW for Left, CW for Right.

H (CW) for Down, B (CCW) for Up. When I fired my first few shots, the impact was rather high. The dial was set to about 9.5, so I dialed it down to 4 and that brought my impact close to my point of aim.

There are no clicks, and the adjustment seems rather coarse. I don’t know much each adjustment is, and was fortunate that my random guess got my close to where I wanted to be. I’ll fine turn this zero at longer distance next time I use this scope.

Shooting off the bench with this easy. Rapid fire offhand felt slow to me. That may be more from my lack of muscle memory with the AK over the design of the scope.

If you were looking for a scope for serious fighting use, I would recommend getting something newer. But this is a proven functional fighting scope. It will get the job done if you need it too.

Optic of the week – GRSC 1-10x Full Spectrum Optic

I just realized as I wrote this title that everything I have ever seen that was named Full Spectrum something or another has been kind of a let down.

Long ago I told Shawn that my holy grail optic would be a 1-10x. But I knew that as soon as I bought one a cheaper, better 1-20x would come out. So if a 1-20x comes out next week, you can thank me for that.

Story I read some years ago said that Fred of GRSC came up with the idea of a horse shoe (or in the past called a flat tire) reticle. That he went to a bunch of different scope companies to sell his reticle to them and they all turned him down. Shortly after, the various scope companies started making their own horse shoe reticles. So Fred went and ordered scopes with his reticle in it to sell.

The 1-10x is the newest optic of his. He specced out his custom reticle to be put in the Atibal 1-10X scope. It comes in the box with a spare battery, flip up covers, a sun shade and a kill flash. At 10 inches long and 21 oz, it is a nice size and not overly heavy.

The oversized power adjustment is awesome. It makes changing the magnification easy. It is my favorite part of this scope.

The turrets are capped. The clicks were easy to tell apart.

The turrets are nice. I’m not sure if I would want to run them uncovered, but they would probably be find if you did. When I zeroed the scope, the windage adjusted just as I expected, I had a great deal more elevation movement than I expected. I’m not sure if I dialed in the wrong adjustment, or if the scope wasn’t performing at expected. If I keep this scope, I’ll do a box test later.

I first used it on a 5.56 upper. When I started trying to zero at 25 yards, I found it rather hard. It seemed like I could either have the target in focus, or the reticle, but not both. Under 4x, I couldn’t make out the reticle, over 7x I the target was too blurry to see. Finally I settled for a blurry target and sighted in quickly. I then slapped it on a 5.45 and fired a couple hundred rounds at 15 yards trying it for speed.

Let us take a look at the reticle:

10X Note the thick horseshoe and the bullet drop reticle set up for M855.
10X illuminated
1X illuminated

The illumination is said to be daylight bright. In shade it showed up well, but once I was out in the Florida sunshine it was not bright enough.

Parallax is suppose to be set at 100 yards. I really struggled with the ocular focus on this scope. I kept fiddling with it as I felt the reticle was a little fuzzy. In the end I think it is the reticle it self that is less than crisp. (Edit – as I was writing this article I played with the ocular focus more. I got it better.) The eye relief seemed fine, but the eye box is small. It was very unforgiving on head placement. If I wasn’t lined up right, the reticle would get fuzzy or have a shadow.

I like the horse shoe reticle, but I feel like this execution could have been done better. The horseshoe is very thick, and obscures part of your target at 10X. At 1X it is very tiny, and I relied more on the large circle than the center horseshoe. The view is pretty good. A little bit of a bubble effect at 1X, but certainly acceptable. (Edit – when I adjusted the ocular focus almost all the way out to get the cross hair crisper, it make the 1X setting appear to be more magnification, the picture was not as flat as before)

I did a bunch of rapid fire with this optic at 15 yards. At first I used the brightest illumination and shooting at a red dot on white paper, the dim red reticle washed out. Turning the illumination off worked better.

I didn’t feel particularly fast when I was using this scope. But I think speed would come with more practice. From 15 yards I shot using 1X, 4X, and 10X. I was shooting a much smaller group with 10x than the other two. I think this might have been due to the reticle being clearer at that magnification. Unfortunatly I didn’t think to bring a timer, so I may have been shooting slower at the higher magnifications and didn’t notice it. I choose to intentionally speed up with the 4X and 10X shooting and that opened up groups.

I wouldn’t call this a proper review. We still don’t know how reliable or durable this scope is. How accurate its bullet drop chart reticle is. Those are very important questions. If I were looking for an optic for a fighting weapon, I spend more would go with a proven product.

If I had to rate this, at the moment I would give it a C-. It is ok, but I wouldn’t call it great. But it is great to see more lower cost 1-X power scopes.