ZT News
ZeroTech 3-18×44 FFP S2H – Rokslide Field Evaluation
The following is a third-party field evaluation of the ZeroTech 3-18×44 FFP S2H Rokslide rifle scope. The format below keeps the evaluator’s notes in a straightforward field-test style so readers can follow the testing sequence, image references, and results.
The scope evaluated was an early prototype manufactured in Japan.
The scope is fantastic with regards to reticle, eyebox, size, turrets, and parallax. It was beyond what Ryan or I had hoped for.
3x:
With the lighting and the textured wall here, it was difficult to get a clear picture of the reticle.
8x:
There are multiple small design items that can be seen that correct issues on other scopes.
Short elevation turret. Index finger touching the tube. It’s not tall.
Low-profile windage. No problem.
Pinky finger clearance.
Drop Evaluation Standard
For context, the test consists of three 18” drops on a mat: one left, one right, and one top, with a shot to check zero after each drop.
Then the same thing is repeated from 36”.
Then three drops on all three sides for nine drops on the last part.
15 drops total.
This is not “abuse.” The 18” drops are not significant. The 36” drops start showing something. When a scope make/model consistently goes through the whole thing without losing zero, and makes it through the high-round-count portion, failures in actual use are almost unheard of.
This one was conducted on semi-packed snow, with a 1/2” padded shooting mat on top.
The rings were degreased and installed with 65 in-lbs on base screws, and 20 in-lbs on ring cap screws.
Initial Mounting and First Drop Attempt
Got back just before dark. Rushed it, mounted one up, and commenced shooting.
Groups initially were odd and larger than the gun’s norm. Stringing, or seeming to jump POI. Finally unmounted and remounted the scope. Groups were a bit smaller, but still not quite right.
With almost no light left, I went ahead and attempted the drop eval.
Top left is 8 shots. Adjusted up .1 mil and left .1. Drop eval is center dot.
This one was conducted on solid frozen ground and a single 1/2” mat, not two pads.
The 9×36” drops shifted off the dot.
Went to the bottom center and fired three. All centered.
Went to the pads and dropped 4 times or so from shoulder to head height, then 2–3 times from shoulder height on the frozen ground.
The third shot went more left, and I noticed the buttstock wiggling.
The screw that holds the buttstock onto the main chassis had gotten loose.
So, inconclusive.
Got back to the house, tightened that up, and evaluated all three properly the next day.
Proper Drop Eval Setup
The T3 shot a 1.7” horizontally strung group with the proof scope. Something is broke somewhere and will have to be tracked down.
Mounted one of the prototype scopes in the BAT Hammerhead .308.
It is not bonded, but has been used to drop-eval scopes. With a NF Milspec, it has about .1 mil +/- shift on 36” drops every once in a while.
The proof group with the new lot number of Federal 308T was 1.5”. That is the worst group I have ever seen a gun shoot that ammo, but still acceptable for checking zero shift.
This drop eval was conducted on hard-packed frozen ground with a single 1/2” padded shooting mat, not two mats as normal for the drop eval.
Scope was bore-sighted and 3 rounds fired.
- Top: first 3 rounds.
- Read reticle and adjusted.
- Left dot: remaining 7 shots.
- Adjusted up .1 and left .2.
- Center dot: next 3.
I adjusted up .1 mil before the drop portion. This was a mistake.
First shot with no drops hit the very top of the 12 o’clock on the dot.
Then I did 15 drops from 36”, not 18”.
The mistake of the last adjustment is seen.
Then I conducted two more rounds of 15 drops at 36”.
For a total of 45 drops from 36” on hard-packed frozen ground.
There was no POI shift from the first shot to the end of 45x 36-inch drops.
I adjusted down .2 mils and shot ten rounds.
Down .2 mils was too much again.
Next was the RTZ portion.
RTZ and Tracking
RTZ:
Adjusting / tracking:
The two dots fell between 7.3 and 7.4 mils. I used 7.4 mils.
Bottom at zero:
At 7.4 mils of elevation:
Spot on.
All shots:
Conclusion:
Scope worked correctly.
Held zero through 45 drops from 36”.
All shots were inside the cone of the gun.
RTZ and tracking were as good as can be shot live-fire in the field.
It did not shift out of the cone for 45 drops.
At least for that, it’s about as good as it gets.
Scope #3
Same gun, ammo, and rings.
Bore-sighted.
Two shots high. Read reticle and adjusted.
Next 8 shots on the left dot.
Drop portion:
Same gun, ammo, rings. Same terrain and mat placement: hard-packed, frozen ground.
Shot on the same dot from above on the initial zero.
15x drops from 36”.
No point-of-impact shift whatsoever.
Post drops:
RTZ:
Apparently rifles get more accurate when you drop them.
Scope #1
Scope #1 was taken off the Tikka and put on the BAT.
Same rifle, rings, and ammo from the last two.
Same surface for the drops.
First, I didn’t boresight and held center of the target well below the dots. It was getting dark and I was rushing. Couldn’t see the hit; it’s the tape.
Then boresighted and two rounds high.
Adjusted and next 8 in the left dot.
Drop eval:
15x drops from 36”.
Same surface and pad as the last two.
No point-of-impact shift whatsoever.
That is all 3 today, and the scopes did exactly what the manufacturer said they would.
Now they get mounted on rifles and start the shooting.
Size and Low-Light Notes
It is a compact thing.
That rifle is the size of a Red Ryder BB gun.
I zeroed it on 18x two minutes before legal light, 30 minutes after sunset.
Two minutes after legal light, 32 minutes past legal sunset.
3x. The pine trees are approximately 150–175 yards.
3x at 30–50 yards.
3x with illumination, about 2/3 max.
Turrets
Elevation is 10 mils per rev, revolution indicated, with a zero stop.
The zero stop is huge. I don’t think I’ve seen one quite like it.
It has three screws around the edges that you loosen to drop.
It is a pin-on-pin design, similar to others, but not quite the same.
Much larger in diameter, and the turret spindle is thicker/bigger.
Windage is 10 mils per rev, marked left and right.
Again, the turret spindle is a thick one under there.
.223 Shooting
The start.
16” .223 in the wood ROKStok Lite.
ADI 55gr SBK.
5x yesterday.
5x today.
The whole thing:
Far left is the first group yesterday.
Read reticle and adjusted.
Put the next five in the top dot.
Those five were shot in near darkness. Used the illumination on the last 2–3 shots.
The three left hits are from yesterday.
Then 5 more today.
Adjusted down .1 and left .1, and put 5 on the bottom dot.
Comparison with Trijicon Tenmile 3-18x44mm
Both at roughly 40 yards.
Tenmile:
Note: it is not this blurry in real life. The camera just refused to focus correctly.
S2H:
The first thing that jumps out is the large difference in FOV between them.
It is noticeable.
Also, while not as much as the photos show, the S2H is brighter, crisper, sharper, with better colors.
Of course, the difference in reticle is apparent.
Comparison with Maven RS1.2
S2H scope versus the best of the three Maven RS1.2 scopes I have.
Maven RS1.2 on 3x:
S2H on 3x:
Again, a noticeable difference in FOV, though the Maven is better than the Tenmile in FOV.
The S2H scope is brighter, sharper, with better color rendition.
Everything is just a bit more muted in the Maven than the S2H, and the Maven has almost a tiny bit of distortion over the whole image.
Zero Checks and Zeroing
.223 again with S2H scope.
Shot more 88gr TMKs to check POI.
6XC check with S2H scope.
For those two scopes, it’s been a couple hundred miles in the truck and about 20 miles on rough forest service road since being zeroed.
Zeroed 6UM with 4-16x ATACR after swapping stock.
First two went pretty high. Adjusted. Three shots low left. Final adjustment: three shots.
Zeroed 6x45mm with S2H scope.
Adjusted up .2, right .1, and slipped turret.
Checked POI with 107gr TMK.
Then trued all of them at 805 yards.
2–4 mph winds.
All trued perfect using Sierra-stated BCs, except the 6UM was high .2 mils, and the .223 with 88gr was low .4 mils.
The .223 was clearly reduced BC due to the low MV and 8” twist.
Flare Conditions
Today: setting sun, pretty nasty flare conditions.
Pictures are a pretty good representation of what was seen.
The NF 4-16x ATACR was maybe 10% better in real life than the pictures show, and is also old. It is one of the first that they made.
The S2H is very close to what it was in real life. It might have been 5% worse than the pictures.
An obvious and noticeable difference.
Both scopes set at 16x.
NF 4-16x ATACR:
S2H:
When not looking at the sun, the images between them were similar.
Sometimes it seemed the NF was better. Sometimes the S2H seemed better.
But, for whatever reason, the S2H controlled glare noticeably better.
Zero checked all three scopes after multiple flights across the country and 1,000-plus miles in trucks with no padding.
Final Field Notes
The scopes did what they were supposed to do.
The drop evals did not show point-of-impact shift.
One scope went through 45 drops from 36” on hard-packed frozen ground with no POI shift.
The other scopes were checked with 15x drops from 36” and showed no point-of-impact shift.
Tracking and RTZ were as good as could be confirmed live-fire in the field.
The scope is compact, has a usable reticle, good eyebox, low-profile controls, and a substantial turret/zero-stop design.
Optically, the evaluator noted strong FOV, brightness, sharpness, color rendition, and glare control compared with the scopes used during the evaluation.
