Out of the box problems with my ZCO 527

Usmcgeek

GySgt
Minuteman
Supporter
Jan 3, 2022
39
29
Mckinney, TX
Not looking to bash any manufacturer here, am looking to see if there have been similar instances to my experience and the best way others have solved these problems.

Yes, I know this is a long post and that there are plenty of people out there running ZCO’s that haven’t had problems, am not looking for input similar to, “I’ve had several and never had a problem”, I’m looking for folks that have had problems to post. Yes, I also know that after searching the forums here that there are a number of people very passionate about ZCO’s, again I am not looking to bash any manufacturer.

The gist:
I bought a new ZCO 527 with a 3X reticle and a new Spuhr mount (SP-6602) for one of my rimfire PRS rings (22LR for those not familiar). Yes, I have a ton of experience mounting scopes and building PRS rifles with high quality glass. I used the Spuhr because of having good prior success with them mounting NF’s and Leupolds on them, plus I needed the extra elevation due to shooting rimfire at distance. No, I didn’t drop, bang, assault or otherwise use this glass as a hammer before I had issues.

Mounting: I centered the reticle bell in the middle of the mount and torqued the ring screws to 18 inch lbs. I don’t like over tightening rings on my glass and yes I know ZCO says you can go up to 25 inch lbs.

I zeroed at a local indoor range and shot some good 10-shot groups, totaling about 100 rounds. I did have to come down 3.4MIL from the factory zero to find my own.

I then shot about 50 rounds over the weekend outdoors at distance to validate DOPE with a few other shooters. While shooting, twice I noticed the reticle “drop” ~4MIL after adjusting elevation between 150yds and 200yds and sending a round. When I say “drop”, I mean that while watching the round land, the reticle dropped ~4MIL at recoil. Both rounds landed at the location the reticle dropped to, ~4MIL below the targett. Both instances were also the first round after adjusting elevation. Initially, I thought it was just me.

Sunday, I shot a PRS match with it at RTSS (love that place). The second stage was at 220yds, 7.9MIL of elevation for my DOPE. First two rounds were ~5MIL low, it surprised me. I adjusted the turret up 5MIL and reengaged. That 3rd round landed in the same spot as the first 2. I adjusted the turret up again 5MIL and the 4th round landed in the same spot as the first 3. I halted my COF and took a 0, didn’t want to introduce more of a safety concern.

I went back to the zero board and after returning the turret to 0, a round landed correctly, dead-nuts at my zero. After adjusting up 1mil and firing, that round landed at 0.3MIL higher than the first, not the 1MIL I expected. I then adjusted up 5 more MIL, 6MIL in total, and that rounded landed at 1.3MIL of elevation, not the 6MIL I expected.

I changed scopes for my old NF and shot the rest of the match, glad I brought it.

After the match, I had 3 other shooters verify the same thing I was seeing. I also adjusted the windage knob Left 6MIL and back about 3 when I heard a loud click inside the reticle bell. Another shooter heard this as well. After dialing everything back to zero and sending a few rounds, impacts were 3MIL left of zero. The reticle had moved 3MIL left from its zero.

I can see something happening like this once in a blue moon, the shocking part of yesterday was that another shooter, with his brand new ZCO 527 came up to me after the match and said he had nearly the same problem I did, that morning, at that same match. 2 brand new ZCOs going down at the same match just doesn’t sound right.

Needless to say, I am very disappointed and I have low confidence running a ZCO again in a match. I do intend to send mine back to ZCO for repair but spending ~$4K on glass and having this type of issue is just a kick in the pants. Is ZCO having a quality problem? Anyone have good advice on repair or mounting? I’d very much like to hear if others have had similar situations and how they were or weren’t corrected.
 
I get the frustration and I am not a ZCO fanboy. But remember not ever scope is going to be perfect from any company out there all the time. Sometimes you get the bad scope. Yes total hassle sending it back. Hopefully you will like it when it comes back.
I totally agree. Anything can ( and often does) happen when dealing with things mechanical. Trust the people at ZCO will make it better than right.
 
I hope you remember how to use iron sights. If you don't have faith in ZCO because you got a lemon, I can show you a failure from every other manufacture to kill your faith in them too. I have had to return a NF and Kahles for example.

Let them take care of it, and then enjoy one of the best optics on the market with confidence..
 
I hope you remember how to use iron sights. If you don't have faith in ZCO because you got a lemon, I can show you a failure from every other manufacture to kill your faith in them too. I have had to return a NF and Kahles for example.

Let them take care of it, and then enjoy one of the best optics on the market with confidence..
Being "old Corps"... I sure do shoot well with iron sights! HA!
 
If indeed there were two people at the match with the same new scope and the same problem, it could actually indicate that all is not well in manufacturing land at ZCO.

At the very least, someone should tag a ZCO rep here so that they can investigate or at minimum report it back to assembly.

Maybe @CSTactical can pass the info on in case this is more than a simple random case.
 
If indeed there were two people at the match with the same new scope and the same problem, it could actually indicate that all is not well in manufacturing land at ZCO.

At the very least, someone should tag a ZCO rep here so that they can investigate or at minimum report it back to assembly.

Maybe @CSTactical can pass the info on in case this is more than a simple random case.
If I knew a rep, I would have. You have a great point though, can some tag them here too please?
 
Not looking to bash any manufacturer here, am looking to see if there have been similar instances to my experience and the best way others have solved these problems.

Yes, I know this is a long post and that there are plenty of people out there running ZCO’s that haven’t had problems, am not looking for input similar to, “I’ve had several and never had a problem”, I’m looking for folks that have had problems to post. Yes, I also know that after searching the forums here that there are a number of people very passionate about ZCO’s, again I am not looking to bash any manufacturer.

The gist:
I bought a new ZCO 527 with a 3X reticle and a new Spuhr mount (SP-6602) for one of my rimfire PRS rings (22LR for those not familiar). Yes, I have a ton of experience mounting scopes and building PRS rifles with high quality glass. I used the Spuhr because of having good prior success with them mounting NF’s and Leupolds on them, plus I needed the extra elevation due to shooting rimfire at distance. No, I didn’t drop, bang, assault or otherwise use this glass as a hammer before I had issues.

Mounting: I centered the reticle bell in the middle of the mount and torqued the ring screws to 18 inch lbs. I don’t like over tightening rings on my glass and yes I know ZCO says you can go up to 25 inch lbs.

I zeroed at a local indoor range and shot some good 10-shot groups, totaling about 100 rounds. I did have to come down 3.4MIL from the factory zero to find my own.

I then shot about 50 rounds over the weekend outdoors at distance to validate DOPE with a few other shooters. While shooting, twice I noticed the reticle “drop” ~4MIL after adjusting elevation between 150yds and 200yds and sending a round. When I say “drop”, I mean that while watching the round land, the reticle dropped ~4MIL at recoil. Both rounds landed at the location the reticle dropped to, ~4MIL below the targett. Both instances were also the first round after adjusting elevation. Initially, I thought it was just me.

Sunday, I shot a PRS match with it at RTSS (love that place). The second stage was at 220yds, 7.9MIL of elevation for my DOPE. First two rounds were ~5MIL low, it surprised me. I adjusted the turret up 5MIL and reengaged. That 3rd round landed in the same spot as the first 2. I adjusted the turret up again 5MIL and the 4th round landed in the same spot as the first 3. I halted my COF and took a 0, didn’t want to introduce more of a safety concern.

I went back to the zero board and after returning the turret to 0, a round landed correctly, dead-nuts at my zero. After adjusting up 1mil and firing, that round landed at 0.3MIL higher than the first, not the 1MIL I expected. I then adjusted up 5 more MIL, 6MIL in total, and that rounded landed at 1.3MIL of elevation, not the 6MIL I expected.

I changed scopes for my old NF and shot the rest of the match, glad I brought it.

After the match, I had 3 other shooters verify the same thing I was seeing. I also adjusted the windage knob Left 6MIL and back about 3 when I heard a loud click inside the reticle bell. Another shooter heard this as well. After dialing everything back to zero and sending a few rounds, impacts were 3MIL left of zero. The reticle had moved 3MIL left from its zero.

I can see something happening like this once in a blue moon, the shocking part of yesterday was that another shooter, with his brand new ZCO 527 came up to me after the match and said he had nearly the same problem I did, that morning, at that same match. 2 brand new ZCOs going down at the same match just doesn’t sound right.

Needless to say, I am very disappointed and I have low confidence running a ZCO again in a match. I do intend to send mine back to ZCO for repair but spending ~$4K on glass and having this type of issue is just a kick in the pants. Is ZCO having a quality problem? Anyone have good advice on repair or mounting? I’d very much like to hear if others have had similar situations and how they were or weren’t corrected.


Does the parallax move freely? If not then it could be the mount. At worse just contact ZCO tomorrow when they are open. Any and every man made product can have a problem. I know this issue is not typical as we have sold thousands. I know you are upset because it’s happening to you, but just give them a call tomorrow so you can get it resolved.

- Richard
 
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If indeed there were two people at the match with the same new scope and the same problem, it could actually indicate that all is not well in manufacturing land at ZCO.

At the very least, someone should tag a ZCO rep here so that they can investigate or at minimum report it back to assembly.

Maybe @CSTactical can pass the info on in case this is more than a simple random case.


No need for me to do anything, they just need to call them tomorrow when they are open.
 
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Does the parallax move freely? If not then it could be the mount. At worse just contact ZCO tomorrow when they are open. Any and every man made product can have a problem. I know this issue is not typical as we have sold thousands. I know you are upset because it’s happening to you, but just give them a call tomorrow so you can get it resolved.

- Richard
Parallax moved smoothly. Sent an email over last night but will call in the morning. Was just shocked that 2 of these went down in the same match. Thanks for the pointer.
 
Not looking to bash any manufacturer here, am looking to see if there have been similar instances to my experience and the best way others have solved these problems.

Yes, I know this is a long post and that there are plenty of people out there running ZCO’s that haven’t had problems, am not looking for input similar to, “I’ve had several and never had a problem”, I’m looking for folks that have had problems to post. Yes, I also know that after searching the forums here that there are a number of people very passionate about ZCO’s, again I am not looking to bash any manufacturer.

The gist:
I bought a new ZCO 527 with a 3X reticle and a new Spuhr mount (SP-6602) for one of my rimfire PRS rings (22LR for those not familiar). Yes, I have a ton of experience mounting scopes and building PRS rifles with high quality glass. I used the Spuhr because of having good prior success with them mounting NF’s and Leupolds on them, plus I needed the extra elevation due to shooting rimfire at distance. No, I didn’t drop, bang, assault or otherwise use this glass as a hammer before I had issues.

Mounting: I centered the reticle bell in the middle of the mount and torqued the ring screws to 18 inch lbs. I don’t like over tightening rings on my glass and yes I know ZCO says you can go up to 25 inch lbs.

I zeroed at a local indoor range and shot some good 10-shot groups, totaling about 100 rounds. I did have to come down 3.4MIL from the factory zero to find my own.

I then shot about 50 rounds over the weekend outdoors at distance to validate DOPE with a few other shooters. While shooting, twice I noticed the reticle “drop” ~4MIL after adjusting elevation between 150yds and 200yds and sending a round. When I say “drop”, I mean that while watching the round land, the reticle dropped ~4MIL at recoil. Both rounds landed at the location the reticle dropped to, ~4MIL below the targett. Both instances were also the first round after adjusting elevation. Initially, I thought it was just me.

Sunday, I shot a PRS match with it at RTSS (love that place). The second stage was at 220yds, 7.9MIL of elevation for my DOPE. First two rounds were ~5MIL low, it surprised me. I adjusted the turret up 5MIL and reengaged. That 3rd round landed in the same spot as the first 2. I adjusted the turret up again 5MIL and the 4th round landed in the same spot as the first 3. I halted my COF and took a 0, didn’t want to introduce more of a safety concern.

I went back to the zero board and after returning the turret to 0, a round landed correctly, dead-nuts at my zero. After adjusting up 1mil and firing, that round landed at 0.3MIL higher than the first, not the 1MIL I expected. I then adjusted up 5 more MIL, 6MIL in total, and that rounded landed at 1.3MIL of elevation, not the 6MIL I expected.

I changed scopes for my old NF and shot the rest of the match, glad I brought it.

After the match, I had 3 other shooters verify the same thing I was seeing. I also adjusted the windage knob Left 6MIL and back about 3 when I heard a loud click inside the reticle bell. Another shooter heard this as well. After dialing everything back to zero and sending a few rounds, impacts were 3MIL left of zero. The reticle had moved 3MIL left from its zero.

I can see something happening like this once in a blue moon, the shocking part of yesterday was that another shooter, with his brand new ZCO 527 came up to me after the match and said he had nearly the same problem I did, that morning, at that same match. 2 brand new ZCOs going down at the same match just doesn’t sound right.

Needless to say, I am very disappointed and I have low confidence running a ZCO again in a match. I do intend to send mine back to ZCO for repair but spending ~$4K on glass and having this type of issue is just a kick in the pants. Is ZCO having a quality problem? Anyone have good advice on repair or mounting? I’d very much like to hear if others have had similar situations and how they were or weren’t corrected.
What did ZCO say after you called and let them know of the issue? Or the retailer you bought it from? Or did you just come here to whine and bitch about a product? You did a tall target test before you took the scope to a match right?
 
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What did ZCO say after you called and let them know of the issue? Or the retailer you bought it from? Or did you just come here to whine and bitch about a product? You did a tall target test before you took the scope to a match right?
I highly doubt ZCO is open and answering the phones on memorial day....

@Jrb572 yes non-locking elevation. That guy is just a jackass, all good
 
I highly doubt ZCO is open and answering the phones on memorial day....

@Jrb572 yes non-locking elevation. That guy is just a jackass, all good
Then wait a day FFS. This is why people don't care what many have to say here. They just run here to blast a company without even giving them a chance to make it right. And I would bet 80% of the time, it's user error or something they did or did not do.

Every product fails. Tangents AI ZCO KAC MDT....name a high end brand and there are failures. Shit happens and the more you shoot the more you see failures.

Instead of running here to shit post a respected company that goes out of its way to take care of its customers...like many other premium brands...dude starts running his face how he doesn't trust them like he's at the town square standing on a soapbox.

If he tested his gear like everyone by now should know to do he would have seen the issue. Who takes a new scope to a match without at least doing a tall target test? Hard to feel bad for someone who set himself up for failure.

It's possible the issue is user error. It's possible there is a assembly/manufacturing defect. Either way at least give the company a chance to figure that out before running here talking about you have no confidence anymore. No one gives a shit about your opinion.

In fact if I was HMFIC around here anyone posting about failed equipment without giving the mfg a chance to make it right first, would get a month long ban. Especially from companies with solid reputations and a history of supporting shooters. It's the main reason reps don't come around here anymore. There used to be a TON, who got run off due to people shitting on them and piling on, many times over non issues.

If you cannot see the irony in someone asking if NLE means Non locking elevation then I don't know what to tell you. Maybe they don't teach what an acronym looks like in public school anymore. They must also stopped teaching how to Google.

Merry Christmas
 
Then wait a day FFS. This is why people don't care what many have to say here. They just run here to blast a company without even giving them a chance to make it right. And I would bet 80% of the time, it's user error or something they did or did not do.

Every product fails. Tangents AI ZCO KAC MDT....name a high end brand and there are failures. Shit happens and the more you shoot the more you see failures.

Instead of running here to shit post a respected company that goes out of its way to take care of its customers...like many other premium brands...dude starts running his face how he doesn't trust them like he's at the town square standing on a soapbox.

If he tested his gear like everyone by now should know to do he would have seen the issue. Who takes a new scope to a match without at least doing a tall target test? Hard to feel bad for someone who set himself up for failure.

It's possible the issue is user error. It's possible there is a assembly/manufacturing defect. Either way at least give the company a chance to figure that out before running here talking about you have no confidence anymore. No one gives a shit about your opinion.

In fact if I was HMFIC around here anyone posting about failed equipment without giving the mfg a chance to make it right first, would get a month long ban. Especially from companies with solid reputations and a history of supporting shooters. It's the main reason reps don't come around here anymore. There used to be a TON, who got run off due to people shitting on them and piling on, many times over non issues.

If you cannot see the irony in someone asking if NLE means Non locking elevation then I don't know what to tell you. Maybe they don't teach what an acronym looks like in public school anymore. They must also stopped teaching how to Google.

Merry Christmas
Up yours. You are always a dick. Fuck off asshole
 
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What did ZCO say after you called and let them know of the issue? Or the retailer you bought it from? Or did you just come here to whine and bitch about a product? You did a tall target test before you took the scope to a match right?
Of course I did a target test. Your post here is “interesting” to say the least.

Clearly reading what I wrote, you’d see that it happened on a holiday weekend when everyone was closed.
 
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Of course I did a target test. Your post here is “interesting” to say the least.

Clearly reading what I wrote, you’d see that it happened on a holiday weekend when everyone was closed.
That is what is known as a rhetorical question. It's meant to make a dramatic point.

Then wait until tomorrow to contact ZCO/who you bought it from..... I mean is it that urgent?
 
That is what is known as a rhetorical question. It's meant to make a dramatic point.

Then wait until tomorrow to contact ZCO/who you bought it from..... I mean is it that urgent?
If you were paying attention (you weren’t) you’d know that he was more asking if anyone else had the same issue and if there was a way to correct it. And he specifically wasn’t trying to bash anyone or start shit.

But thanks for paying attention. 👍🏻
 
n fact if I was HMFIC around here anyone posting about failed equipment without giving the mfg a chance to make it right first, would get a month long ban.
1748307239766.jpeg
 
Then wait a day FFS. This is why people don't care what many have to say here. They just run here to blast a company without even giving them a chance to make it right. And I would bet 80% of the time, it's user error or something they did or did not do.

Every product fails. Tangents AI ZCO KAC MDT....name a high end brand and there are failures. Shit happens and the more you shoot the more you see failures.

Instead of running here to shit post a respected company that goes out of its way to take care of its customers...like many other premium brands...dude starts running his face how he doesn't trust them like he's at the town square standing on a soapbox.

If he tested his gear like everyone by now should know to do he would have seen the issue. Who takes a new scope to a match without at least doing a tall target test? Hard to feel bad for someone who set himself up for failure.

It's possible the issue is user error. It's possible there is a assembly/manufacturing defect. Either way at least give the company a chance to figure that out before running here talking about you have no confidence anymore. No one gives a shit about your opinion.

In fact if I was HMFIC around here anyone posting about failed equipment without giving the mfg a chance to make it right first, would get a month long ban. Especially from companies with solid reputations and a history of supporting shooters. It's the main reason reps don't come around here anymore. There used to be a TON, who got run off due to people shitting on them and piling on, many times over non issues.

If you cannot see the irony in someone asking if NLE means Non locking elevation then I don't know what to tell you. Maybe they don't teach what an acronym looks like in public school anymore. They must also stopped teaching how to Google.

Merry Christmas
Please just shut the fuck up.
 
I have had a good number of ZCO scopes pass through my hands over the years. I have never seen anything resembling a systemic problem with the 5-27x ZCO. Everyone makes a lemon once in a while, so I would not draw too many conclusions out of it.

They'll fix it. For what it is worth, I have seen far more problems with Spuhr mounts than with ZCO scopes.

As far as the other shooter with the same problem goes... it is statistically unlikely, but there could be a bad batch for some reason. I'd be very surprised, but it is possible. It is possible he had the same problem. It is even more possible that he was attributed a bad day to the scope. That happens quite a bit.

The issues with your scope look to be carefully observed, so there is a good chance there are issue with it.

ILya
 
I have had a good number of ZCO scopes pass through my hands over the years. I have never seen anything resembling a systemic problem with the 5-27x ZCO. Everyone makes a lemon once in a while, so I would not draw too many conclusions out of it.

They'll fix it. For what it is worth, I have seen far more problems with Spuhr mounts than with ZCO scopes.

As far as the other shooter with the same problem goes... it is statistically unlikely, but there could be a bad batch for some reason. I'd be very surprised, but it is possible. It is possible he had the same problem. It is even more possible that he was attributed a bad day to the scope. That happens quite a bit.

The issues with your scope look to be carefully observed, so there is a good chance there are issue with it.

ILya
Great feedback, thank you. Lemons happen no matter how high quality products are. Will see what they say when I get it over to them.
 
A few years ago there were reports of ZCO issues with Spuhr mounts, but I think in all cases the parallax was affected.

And if I recall correctly, there have been some defective Spuhr mounts but I don't know if they overlapped in time.
Thanks, am considering the mount as well if the glass checks out. I did hear the loud click mentioned in my post without the glass in the spuhr though. Any recommendations on an alternate mount? Couple buddies at the match recommended going with a 419.
 
Thanks, am considering the mount as well if the glass checks out. I did hear the loud click mentioned in my post without the glass in the spuhr though. Any recommendations on an alternate mount? Couple buddies at the match recommended going with a 419.
Yeah, a 419 is a good piece of kit. Somehow I missed the Click. That would account for the point of impact change. Still a chance of a scope issue but dump the Spuhr and send it in.
 
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