Q&A for ZCO 4-20x50mm Field Eval

[MidGAHunter]

Just wanted to pass this along before everyone thinks they should sell their ZCO on n=1.

Form said he wants to retest it in better rings. I didn't take the initial eval as a "these scopes don't work" as it is a sample of 1 AND Form himself said he wants to repeat the test in better rings. If it fails in better rings, then there may be something to it. Also, @Conrad I appreciate you adding this info. That being said, any chance you'll perform the full drop test on 1 or 2 of your ZCOs? We'd ALL love more data. Thanks for your input!

 

[Conrad]

Form said he wants to retest it in better rings. I didn't take the initial eval as a "these scopes don't work" as it is a sample of 1 AND Form himself said he wants to repeat the test in better rings. If it fails in better rings, then there may be something to it. Also, @Conrad I appreciate you adding this info. That being said, any chance you'll perform the full drop test on 1 or 2 of your ZCOs? We'd ALL love more data. Thanks for your input!

I was more replying to some of the comments alluding to possibly selling their zco after this.

I’d say my first 4-20 has survived a pretty good knock from falling out of kubota and zero held, and that scope us continue to be great in hunting, targets and one run n gun match. I think I heard on the pod they are dropping on grass from 18” and maybe 36”? Is that with a rifle attached. I didn’t fully gather that?

 

[MidGAHunter]

Scope Field Eval Explanation and Standards

This will be about the “why” of the field evaluations- specifically the drop “tests”. Let’s have a thought experiment. Let’s say you have spotted a buck across a valley, planned and executed a stalk which when you get to the last little knob up ahead, will put you within 400-450 yards of the...

rokslide.com

@Conrad

 

[Ryan Avery]

I was more replying to some of the comments alluding to possibly selling their zco after this.

I’d say my first 4-20 has survived a pretty good knock from falling out of kubota and zero held, and that scope us continue to be great in hunting, targets and one run n gun match. I think I heard on the pod they are dropping on grass from 18” and maybe 36”? Is that with a rifle attached. I didn’t fully gather that?

I dropped it on soft dirt on a pad. Like most scopes, the shift happened on the parallax drop.

 

[4th_point]

Additionally the ZCO fasteners are T20 and T25, very good in my opinion. Way better than the chincy Spuhr screws--those blow my mind.

Thanks for the info, Conrad.

Do you know the size of the threaded portion of the fastener? T20 and T25 tells us the star drive size, not the screw size. Sometimes the Torx size can give you the screw size, especially with common hardware because of torque limits for each, but when it comes to firearm screws there are a lot of oddballs!

 

[Conrad]

Thanks for the info, Conrad.

Do you know the size of the threaded portion of the fastener? T20 and T25 tells us the star drive size, not the screw size. Sometimes the Torx size can give you the screw size, especially with common hardware because of torque limits for each, but when it comes to firearm screws there are a lot of oddballs!

Yeah good point. I'll have to remove one to measure, but initial impression it seemed like a quality screw. One thing to note is axial "clamping" force actually goes up the smaller the bolt diameter is for a given torque value.

 

[Formidilosus]

Updated.

 

[kkp005]

Updated.

Ouch. That’s an expensive paper weight.
Thanks for the evaluation

 

[RussDXT]

Neck and neck with the Bushnell .22 scope. Wow.

 

[Formidilosus]

Again, until another set of rings are tried, I wouldn’t take anything definitive from it.

 

[Diced]

Again, until another set of rings are tried, I wouldn’t take anything definitive from it.

What rings are you guys going with next? Arc?

 

[Formidilosus]

What rings are you guys going with next? Arc?

Not sure. Probably won’t be ARC, will likely be the simplest pic rings made.

 

[Lawnboi]

Not sure. Probably won’t be ARC, will likely be the simplest pic rings made.

OT but have you drop tested any arc rings? I’m a fan of the simplicity and havnt personally had issues with them, but im only dropping my rifles by accident

 

[Formidilosus]

OT but have you drop tested any arc rings? I’m a fan of the simplicity and havnt personally had issues with them, but im only dropping my rifles by accident

Not in the full eval as laid out here. Used them years ago without any issues that I remember.

 

[philys21]

I have a ZCO in Hawkins rings on my prs rig and just about finished it’s second year without needing the zero adjusted from banging it around on props, traveling in the back of trucks, and flying.

This past weekend my gun was knocked off a prop and fell in between steel pipes and the gun was suspended from the elevation turret and still didn’t lose its zero. i have 2 more setup in Spuhr mounts with no issue.

 

[4th_point]

"I have a ZCO in Hawkins rings on my prs rig"...

"i have 2 more setup in Spuhr mounts with no issue."

Thanks for the information.

Sounds like an opportunity to increase the sample size +3. With Ryan's, that would be a total of 4.

Plus add the Hawkins and Spuhr to the variables.

Would you be willing to perform the drop eval and document it in this thread?

 

[Ryan Avery]

I have a ZCO in Hawkins rings on my prs rig and just about finished it’s second year without needing the zero adjusted from banging it around on props, traveling in the back of trucks, and flying.

This past weekend my gun was knocked off a prop and fell in between steel pipes and the gun was suspended from the elevation turret and still didn’t lose its zero. i have 2 more setup in Spuhr mounts with no issue.

You went two years without adjusting turrets on a PRS Rifle?

 

[philys21]

You went two years without adjusting turrets on a PRS Rifle?

not needing to change my zero yes.

 

[slim23]

I guess mounting them in same Brand of rings as the scope manufacturer makes sense but I seen a lot less zero problems when I went to sphur 1 piece mounts. And yes that’s what I use in my hunting rifle for the same reason that you are testing scopes

 

[4th_point]

That's super interesting because some assume that the parallax failures are caused by Spuhr mounts.

The parallax failures do not seem to be infant mortality though, but a longer term durability issue that presents itself as wonky parallax function that stops working altogether.