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Zero Compromise ZC840 8-40x56 starting to ship to CS Tactical!

I'm glad I've held off on my 3rd ZCO this long! The price compared to the new current norm for the 5-27 is pretty competitive to me, at least relatively speaking. A few things I am curious about:
1. Is there an increase in FOV with the 8-40 over the 5-27 at equivalent powers?
2. Will the reticle thickness be thinner than the 5-27 at equivalent power?
3. Really curious if there will be a slight optical advantage when comparing the 8-40 and 5-27 at typical powers (say 12-20) since that seems to have been noted with other scopes that have 5-25 and 7-35 or similar versions.
ETA: I just noticed the 15m parallax. Super cool! That nice treat for rimfire, especially if DOF is as awesome at typical of ZCO

All that information will be released in the future when ZCO has a chance, the public release was a little rushed since the ZC840 was accidentally leaked on their website. 🤯
 
As for the 28 mils on elevation, that is just about what I would expect for scaling up the magnification given the existing ZCO designs. As mentioned in the EDC podcast, ZCO initially went with a larger 36mm tube on their 5-27 power in order to both get the 35mils elevation they desired and still have the size erector lenses they also desired for the excellent optical performance they were looking to get. In an internally adjusted scope, there isn't really a work around for this three pronged dilemma. Going with higher magnification in a design decreases your elevation, going with a smaller erector lens system increases your elevation but decreases your optical performance, going with a bigger tube gives you more room but has it's limitations as being off center on the lens system still degrades optical performance. This ZC840 appears in line with other high magnification internally adjusted scopes in elevation to me based on the manufacturers published specifications.

Not trying to start a fight, just trying to learn. If this ZCO is constrained by its size as far as amounts of adjustment are concerned, how does the March 5-42 fit so much more adjustment? They advertise (I don't have one, just reading) 40 mils of elevation, wider mag range, less weight, shorter body, and more FOV even at the higher elevation with a 34mm tube. Are the ZCO internals just that much more beefy? Where is the compromise (pun intended)?
 
From what I've been told, the closer you get to the extents of the erector cell (and magnification range), the more the optical quality can suffer. You can see this with a lot of economical scopes where the image gets flat and washed out when you're fully zoomed in or elevation is dialed way up. Some would just set the limits to where the optical quality is maintained or they do some better engineering and manufacturing to prevent image degradation.
 
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More information to be released soon! Here is a dedicated thread to talk about ZCO's fantastic offering :cool:
Please PM us your information to get in line or ask any other questions :)

Pre-Order here: https://www.cstactical.com/zco-8-40x56-zc840-riflescope

Pricing will be $4,150.00 to $4,625.00 for the Tremor 5 reticle


View attachment 7776250
Interesting that the elevation adjustment is 7 mils less on a higher power scope that is presumably designed for ELR applications which would require a larger elevation and windage adjustment capability.

Any comments on why that is?
 
Interesting that the elevation adjustment is 7 mils less on a higher power scope that is presumably designed for ELR applications which would require a larger elevation and windage adjustment capability.

Any comments on why that is?
Probably the same reason the mk5 3-18 has more elevation available then their 5-25 and 7-35 counterparts

That reason I'm not completely clear of but I'm sure someone with a better understanding then me can explain it
 
Interesting that the elevation adjustment is 7 mils less on a higher power scope that is presumably designed for ELR applications which would require a larger elevation and windage adjustment capability.

Any comments on why that is?
Look at my post a few above yours.
 
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All that information will be released in the future when ZCO has a chance, the public release was a little rushed since the ZC840 was accidentally leaked on their website. 🤯
Was it really an accident 😉. Personally I think these leaks are beneficial as they create a buzz and excitement within the industry.
 
Not trying to start a fight, just trying to learn. If this ZCO is constrained by its size as far as amounts of adjustment are concerned, how does the March 5-42 fit so much more adjustment? They advertise (I don't have one, just reading) 40 mils of elevation, wider mag range, less weight, shorter body, and more FOV even at the higher elevation with a 34mm tube. Are the ZCO internals just that much more beefy? Where is the compromise (pun intended)?
In brief, March is prioritizing elevation above everything else. This means a shorter scope with very short depth of field and less than ideal image quality at the edges of travel. ZCO seems to be prioritizing an insane depth of field at the expense of a longer scope and less travel, and therefore not needing to worry as much about image quality drop off.

March’s field of view seems to be largely a result of a super optimized eyepiece design taking full advantage of the shorter scope. With a longer scope you need an impractically larger tube, and need to worry about optical effects to get the full field of view to your eye. I wouldn’t be surprised if eye relief also strongly came into play.
 
Not trying to start a fight, just trying to learn. If this ZCO is constrained by its size as far as amounts of adjustment are concerned, how does the March 5-42 fit so much more adjustment? They advertise (I don't have one, just reading) 40 mils of elevation, wider mag range, less weight, shorter body, and more FOV even at the higher elevation with a 34mm tube. Are the ZCO internals just that much more beefy? Where is the compromise (pun intended)?

March has always put a high premium on their numbers. Low weight, small size, huge erector ratios, large travel, etc. The compromise you mentioned is simply optical performance. The March scopes I have seen, and I have not seen the most recent designs, though I have seen many, did not perform in line optically with other scopes in their price range. They were not bad performers, just more like one step down. My take is that with March you get stats better than alpha, at alpha prices, but with a step down in optical performance.

On a side note, do you guys think ZCO, TT, Minox, and S&B (most of the time at least) are designing to optimize stats? Boy, they all must really suck at it. There are far lower cost scopes with much bigger erector ratios, larger elevation travel, lighter weight and likely many other stats. For the most part, they are designing to get the best optical performance while still making some particular benchmark with regard to the stats. Say, how optically good can I make my base model high power rifle scope while still having at least a 5x erector ratio and getting 35mils of travel while coming in under $4k (no idea if that was the criterion for the ZC527 but expect something along those lines.)

I liked your pun on compromise BTW. It reminded me of what I often think when I see the "Zero Compromise" written on the box. All optical design is compromise. No amount of spending gets you out of that even if you weren't considering the spending itself a compromise. I guess it's a hell of a lot catchier than "Best Compromises Optics."
 
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Ya, I'm not spending an hour listening to that.

It either needs to be a 2nd focal plane MOA reticle to appeal to the F-Class guys, or it needs to be an ELR 1st focal plane MIL scope with a lot of elevation. This is like some kind of hybrid that I honestly don't know who it is going to appeal to.

With a 36mm Main tube, the only reason I can see them not giving it 35+ mils of elevation is because they needed to keep the reticle optically centered because once it moves too far to either edge, the clarity and eye box go to shit.

I'd love to hear from ZCO why it only has 28mils and who this scope is designed for.
The exact same people that run atacr 7-35s are going to loose their minds over this scope. Which is pretty much any prs/long range tactical competitor, long range hunter/enthusiast. But yeah, going to be a hard one to figure out who would want such a trash scope with only 28mils of elevation. Lol.
 
I would like to see how the March Genesis 6-60x scope performs since all the elevation travel is external (114 mils elevation).
But for $6k + I'll wait for Ilya to hopefully one day do a full review on it.

It will be interesting to compare this ZCO scope up against the S&B 5-45 and 12-50 and see how they look optically side by side.
 
There are so many companies throwing everything at their scopes at one time like 8-10X erector, short and/or lightweight yet when it hits the market and people get it in hand they end up complaining. ZCO and many other proven premium optics have stuck with 4-6X erectors and the formula necessary to provide an optimal experience overall.
 
I doubt that anyone commenting on my posts about the lack of elevation have much ELR experience so here you go.

I run an ATACR 7-35 on a 0-20 EraTac base set on 10 mils for a 100 yard zero with 35 miles left in the turret. This leaves my EraTac with an additional 10 mils at my disposal. My Charlie Tarac is set to 50 mils.

0-35 mils - I use the turret
35-45 mils - turret and EraTac
45-50 mils - turret, EraTac, holdover on reticle (5 mils of holdover)
50-85 mils - Tarac and turret
85-95 mils - Tarac, turret, and EraTac
95+ mils - add holdover or get a second Tarac

Assuming you loose a couple mils to get a 100yard zero, this new scope will give somewhere between 25-29 mils on the turret making hitting all the elevation ranges even more difficult than it already is. It’s not that it can’t be managed with multiple Taracs, it’s just a pain in the ass.

In my opinion, anything claiming to be a true ELR scope should have at least 35 mils. Not to mention a 40 power scope is pretty much useless at these ranges due to mirage. I’d rather they made a 35 power scope with 40 mils of travel. It would have been far more useful.

My dope in yards:
2500 - 28.5 mils
3000 - 42.8 mils
3500 - 60.6 mils
4000 - 81.6 mils
4500 - 106.1 mils

Regarding the March Genesis, completely useless. Tried one and the damn thing stares straight into the barrel at high elevation. Now you need to buy a Delta Tarac which eliminated the point in buying the scope in the first place.

ATACR 7-35 is still the king of ELR.

Show me your dope, distances, and calculations for how you hit all the elevation ranges.
 
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ATACR 7-35 is still the king of ELR.

Though this is not a ZC840 vs. the 7-35 ATACR thread, it should be noted that the ATACR is listed as 29 mils of adjustment to the ZC840's 28 mils.

And no I (Richard) personally don't have your experience with ELR, but others here at our shop do.
 
Though this is not a ZC840 vs. the 7-35 ATACR thread, it should be noted that the ATACR is listed as 29 mils of adjustment to the ZC840's 28 mils.

And no I (Richard) personally don't have your experience with ELR, but others here at our shop do.
It has 37.5 mils. Why NF doesn’t list it as such you will have to ask them. NF will tell you the same. Both of my 7-35s have it, as well as the three my shooting buddies own.

It’s been discussed here in the boards several times.

And you’re right, I’m not here to say mine is better than yours or get into a NF vs ZCO argument. Just reiteration what I said on the first page that they missed the mark on this scope before everyone piled on me and stating my case.

ZCOs are great, but in my opinion, they completely missed the mark for their target audience.
 
I doubt that anyone commenting on my posts about the lack of elevation have much ELR experience so here you go.

I run an ATACR 7-35 on a 0-20 EraTac base set on 10 mils for a 100 yard zero with 35 miles left in the turret. This leaves my EraTac with an additional 10 mils at my disposal. My Charlie Tarac is set to 50 mils.

0-35 mils - I use the turret
35-45 mils - turret and EraTac
45-50 mils - turret, EraTac, holdover on reticle (5 mils of holdover)
50-85 mils - Tarac and turret
85-95 mils - Tarac, turret, and EraTac
95+ mils - add holdover or get a second Tarac

Assuming you loose a couple mils to get a 100yard zero, this new scope will give somewhere between 25-29 mils on the turret making hitting all the elevation ranges even more difficult than it already is. It’s not that it can’t be managed with multiple Taracs, it’s just a pain in the ass.

In my opinion, anything claiming to be a true ELR scope should have at least 35 mils. Not to mention a 40 power scope is pretty much useless at these ranges due to mirage. I’d rather they made a 35 power scope with 40 mils of travel. It would have been far more useful.

My dope in yards:
2500 - 28.5 mils
3000 - 42.8 mils
3500 - 60.6 mils
4000 - 81.6 mils
4500 - 106.1 mils

Regarding the March Genesis, completely useless. Tried one and the damn thing stares straight into the barrel at high elevation. Now you need to buy a Delta Tarac which eliminated the point in buying the scope in the first place.

ATACR 7-35 is still the king of ELR.

Show me your dope, distances, and calculations for how you hit all the elevation ranges.
While I agree this scope doesn’t have the elevation I’d want in elr competition, it’s not necessary to have 35 mil to be a elr competition scope.
I’ll hide 100 moa scope as an example. Let’s use the tacom bravo tarac as our elevation tool of choice. 100 moa scope is pretty easy to find. Zero 100 moa high at 100 using the bravo in reverse. That gets you through your firs 100 of travel, about 2850yd. You need your next 100 so you crank your scope back to zero abs go through the turret adjustment again. That gets you to 200 moa or about 3675yd. Now for your last 100, to get you to 300 moa, you zero your turrets and put the bravo on in the normal orientation. That gets to about 4300. Now, this is all at My current -1840 da. Want to see how that works at normal comp da?

You’re far from the only elr shooter on this forum. Not nearly as special and superior as you think you are. @Steel head @oneshot.onehit want to add anything since we don’t shoot far enough to run out of elevation? 😂
 
While I agree this scope doesn’t have the elevation I’d want in elr competition, it’s not necessary to have 35 mil to be a elr competition scope.
I’ll hide 100 moa scope as an example. Let’s use the tacom bravo tarac as our elevation tool of choice. 100 moa scope is pretty easy to find. Zero 100 moa high at 100 using the bravo in reverse. That gets you through your firs 100 of travel, about 2850yd. You need your next 100 so you crank your scope back to zero abs go through the turret adjustment again. That gets you to 200 moa or about 3675yd. Now for your last 100, to get you to 300 moa, you zero your turrets and put the bravo on in the normal orientation. That gets to about 4300. Now, this is all at My current -1840 da. Want to see how that works at normal comp da?

You’re far from the only elr shooter on this forum. Not nearly as special and superior as you think you are. @Steel head @oneshot.onehit want to add anything since we don’t shoot far enough to run out of elevation? 😂
That’s what I do
Dial+reticle then when I run out of that (about 2800ish yards) slap on my Charlie tarac and start at 0 again.
That gets me out to 4100 yards.
I never have to change my stock settings doing that.

I have my Charlie tarac set at 35 mils but set it higher for my 7 mm or my buddy’s 338.

As for appropriate ELR scopes, just give me decent glass, a not retarded reticle and 25-30 mils of a elevation I can trust
 
I doubt that anyone commenting on my posts about the lack of elevation have much ELR experience so here you go.

I run an ATACR 7-35 on a 0-20 EraTac base set on 10 mils for a 100 yard zero with 35 miles left in the turret. This leaves my EraTac with an additional 10 mils at my disposal. My Charlie Tarac is set to 50 mils.

0-35 mils - I use the turret
35-45 mils - turret and EraTac
45-50 mils - turret, EraTac, holdover on reticle (5 mils of holdover)
50-85 mils - Tarac and turret
85-95 mils - Tarac, turret, and EraTac
95+ mils - add holdover or get a second Tarac

Assuming you loose a couple mils to get a 100yard zero, this new scope will give somewhere between 25-29 mils on the turret making hitting all the elevation ranges even more difficult than it already is. It’s not that it can’t be managed with multiple Taracs, it’s just a pain in the ass.

In my opinion, anything claiming to be a true ELR scope should have at least 35 mils. Not to mention a 40 power scope is pretty much useless at these ranges due to mirage. I’d rather they made a 35 power scope with 40 mils of travel. It would have been far more useful.

My dope in yards:
2500 - 28.5 mils
3000 - 42.8 mils
3500 - 60.6 mils
4000 - 81.6 mils
4500 - 106.1 mils

Regarding the March Genesis, completely useless. Tried one and the damn thing stares straight into the barrel at high elevation. Now you need to buy a Delta Tarac which eliminated the point in buying the scope in the first place.

ATACR 7-35 is still the king of ELR.

Show me your dope, distances, and calculations for how you hit all the elevation ranges.

Here you go, problem solved...

0-25 mils - Turret
25-35 mils - turret and EraTac
35-40 mils - turret, EraTac, holdover on reticle (5 mils of holdover)
40-75 mils - Tarac and turret
75-85 mils - Tarac, turret, and EraTac
85+ mils - add holdover or get a second Tarac

Personally I don't like moving anything mechanically optics wise other than precise controls internal to a scope and not externally like an Eratac mount but that's just me. If ELR was that significant to you I'd rock multiple Prisms in order to achieve the elevation gain needed. Also no one can design a scope that fits everyone's needs exactly, this should be pretty common sense. They chose optical performance over maximum available elevation.
 
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While I agree this scope doesn’t have the elevation I’d want in elr competition, it’s not necessary to have 35 mil to be a elr competition scope.
I’ll hide 100 moa scope as an example. Let’s use the tacom bravo tarac as our elevation tool of choice. 100 moa scope is pretty easy to find. Zero 100 moa high at 100 using the bravo in reverse. That gets you through your firs 100 of travel, about 2850yd. You need your next 100 so you crank your scope back to zero abs go through the turret adjustment again. That gets you to 200 moa or about 3675yd. Now for your last 100, to get you to 300 moa, you zero your turrets and put the bravo on in the normal orientation. That gets to about 4300. Now, this is all at My current -1840 da. Want to see how that works at normal comp da?

You’re far from the only elr shooter on this forum. Not nearly as special and superior as you think you are. @Steel head @oneshot.onehit want to add anything since we don’t shoot far enough to run out of elevation? 😂
Well said Geno
My setup is a little different while using the Gen II Razor, I am able to use the full 28.5 mils of dial adjustment and my hold over in the reticle combined with the adjustment in the Warner Base which is spot on to push out past 4200 in the Kansas DA while still aiming at the target. Its very repetitive and accurate while adjusting and works for what I need and expect as far as accuracy. I do like the fact that I don’t have to have a additional rail mounted on the rifle and carry the Charlie with my gear to the line its bad enough caring everything now. Don’t take me wrong the Charlies have their place in ELR and work well. The only chatter I heard or seen in the 2021 was the importance of checking and recording the offset in windage that changes at distance with the Charlie’s mounted that some of the shooters have found when getting into the 2500 to 4000+ range that they used to assume was just windage correction errors. Some can say that its not a big deal and wind calls are luck at these distances. But if you did your best on calculating wind the offsets it can be a deal breaker on the points lost on a first round hit. I’m on the road now and when I get home the Gen III will get mounted on my rifle I for one maybe its the older eyes will take all the magnification I can use that mirage will allow in order to catch a impact placement on the plate or impact in the dirt next to a target that my spotter might of missed. I am also happy to see the extra travel in the scope its self.
The cool part is the industry has been pushed hard in the ELR community and there are many options today that will allow any shooter to participate and have a great time pulling some trigger

Osoh
 
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It has 37.5 mils. Why NF doesn’t list it as such you will have to ask them. NF will tell you the same. Both of my 7-35s have it, as well as the three my shooting buddies own.

It’s been discussed here in the boards several times.

And you’re right, I’m not here to say mine is better than yours or get into a NF vs ZCO argument. Just reiteration what I said on the first page that they missed the mark on this scope before everyone piled on me and stating my case.

ZCOs are great, but in my opinion, they completely missed the mark forwhat I'm assuming their target audience is.
Fixed the last sentence for you ;)
 
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I'm glad I've held off on my 3rd ZCO this long! The price compared to the new current norm for the 5-27 is pretty competitive to me, at least relatively speaking. A few things I am curious about:
1. Is there an increase in FOV with the 8-40 over the 5-27 at equivalent powers?
2. Will the reticle thickness be thinner than the 5-27 at equivalent power?
3. Really curious if there will be a slight optical advantage when comparing the 8-40 and 5-27 at typical powers (say 12-20) since that seems to have been noted with other scopes that have 5-25 and 7-35 or similar versions.
ETA: I just noticed the 15m parallax. Super cool! That nice treat for rimfire, especially if DOF is as awesome at typical of ZCO
When comparing the field of view in dis-similar powered scopes multiply the field of view by the power as such:
ZC840
low power 8 x 14.8 = 110.4
high power 40 x 3 =120

ZC527
low power 5 x 21 = 105
high power 27 x 4.5 = 121.5

ZC420
low power 4 x 28 = 112
high power 20x 6 = 120

These numbers, which are a good bit like the field numbers in microscopy, provide a good basis for comparing the fields of view for scopes that aren't quite the same power. I have noticed it is typical for the high power number to be a bit higher than the low power one though I am not sure why this is. It does mean that you have to do both the high and low numbers for each scope and compare high to high and low to low. In the case of the ZCO line, the numbers are quite close across the whole of the ZCO series which I would expect as these probably all use the same, or very close eyepieces. Based on this you can expect very close numbers on the FOV of the ZC840 to the ZC527 when they are in overlapping power ranges.

As for your other questions, I don't haven any useful information.
 
It looks like 840 has the 35 Mils turret. So what is the elevation adjustments 28 or 35? Lol
 
The concern about having 37 mils of adjustment is how accurate are the clicks when you’re in that extended range and what does the image look like? Can you use the windage knob at all?