Accuracy/Optics question

What is the proper way to zero a red dot with a separate magnifier? I have 3 AR platform rifles, one with the red dot. I’ve been able to zero the two with scopes and shoot consistantly with them, but the red dot is a mess.
How I zeroed - 25yds in the backyard with a laser bore sighter, gun in a stand to line up. Then I shot at 50 yards and adjusted, then did the same at 100 except for the 22. The red dot was zeroed without the magnifier in play. Then I swung in the magnifier and the whole view was way off to the right, so I used the windage and elevation to center the sight picture. Shot some matches yesterday and shot a pretty tight group but forgot there was one in the chamber and took six shots. Targeting on the bullseye, the group was centered, but low. Moved the dot down 4 clicks and at 50 yards, on the bullseye and I’m now 8" to the right, but higher. This was without the magnifier. Moved dot another 4 to the left, now closer to center, but now spread out 4" vertically. 4 more to the left and closer to center, but 3-4" higher. The optic is a Riton X1 Tactix RRD red dot with the matching X1 Mag 3, both are mounted on the upper receiver (not on the handguard. One other thing I’m noticing is that there seems to be more play between the upper and lower receiver than my other two. I’m thinking that could be the issue, but I’m not that experienced, so time to get some expert opinions

Here a pic of the targets that didn’t upload .

If I understand the question correctly…
From what I have read and experienced, the magnifier does not (should not) affect zero /POI/POA at all. My 3X Vortex has adjustments on it to “Center” the window but does not affect anything else. You should not adjust windage / elevation on the red dot or hologram sight for the magnifier.

EDIT: I’m not really an expert, but looked up your Riton, it is a budget line. Mixed Amazon reviews. Most times budget line stuff is GTG, but if your experiencing issues maybe send it in for replacement.

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Thanks for confirming that, that was how I thought it worked. The more I think about it, I’m leaning towards the sloppiness in the fitment has something to do with the issue along with my lack of experience but yet I can still get some consistancy, just not on target. Strange.

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Either your mount or the low end red dot won’t hold zero after you shoot the firearm. Both are easy to check. The magnifier has no influence on the sight’s zero.

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A red dot is appropriate for 25 yards. 50 at best if it’s a high end optic. Prismatic maybe 100 yards if you are very skilled. Did you say you are shooting 22LR with this RDS? If so at 100 yards the drop is 5-6 inches and 22LR ammo can be variable/unpredictable at that distance unless it’s match grade.

What bore sighter did you use?

No, the red dot is on my AR 15, my 22 has a Primary Arms scope. I have a couple different brands of bore sighters for various calibers. Sightmark and another brand I can’t remember at the moment. (I’m not at home). Thought the Riton was a mid level piece. Thinking about pulling it off and checking zero with the irons to eliminate the loose fittment as a contributing factor.

Those in-chamber lasers are all over the place too. They do get you on paper a little faster and you can finish the sight-in the old fashioned way. I have a plastic box full of those things. Most of them Sightmark. I’ve found there’s pretty wide variance in their accuracy. You may get one with the laser properly centered in the brass, you may not. After resisting it for a long time, I finally broke down and bought a SiteLite Ultra. Not cheap but it works like a champ. And it’s green laser. You can see it at 100 yards in daylight.

Anyway… Judging by your description my guess is the RDS isn’t holding zero or you need to torque the mount. Also make sure the rail is installed correctly if it isn’t integral to the upper. Good luck!

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Compared to the $39.00 red dots, I suppose so… :smiley:

Back at home (mother in law"s birthday)
The Sightmark I have is 9mm, the rifle calibers are Site Right. I did wonder about their accuracy, so I did a little test - put a dot with a marker on the outside edge & oriented the dot at the 12 o’clock position, closed the action and aligned the reticle to the dot. Opened and closed the action a few times rechecking that it hadn’t moved. Then I turned the dot to 3, 6 & 9 o’clock and did the same thing each time, checking that the dot was still on the reticle, which it was on the 223 and 308. Couldn’t do it with the 22 because it’s so small that the batteries won’t fit in it so it has a separate battery pack with a wire. That still got me on paper and I was able to take shots and walk it in from there. Will do a test alternating between taking a few shots and check with the bore sighter to see if it’s holding or moving. Will also check zero on the irons as well. Thanks much for the insight on this, really appreciate it!

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Back for round 2 of trying to get this figured out. So, after the last shots, I went back to square 1 - checked the zero of the RD with the laser at 25 yds. - POA (Red Dot) was very close on elevation, but 3.5-4" to the left of the laser. Did the laser orienting/rotating test to make sure it was consistent in all positions, which it was. I also re-zeroed the iron signs to the laser. Made a discovery in doing that - to get the dot over the front post, I had to move the rear windage almost all the way to the left to get it lined up.


Checked the red dot by scanning to various trees out further than the 25 yds to the building with my target. Everything looked good. Went to the range and took some shots at 50 yds (slight headwind) and the results were not what I was expecting.

1st group was 6" low & 5" to the left, 2nd was off in the same direction but the grouping was non existent. For the 3rd group, I switched to .556 to see if there was any difference and replicated the 1st shot group, tighter, but still off by the same amounts. Odd because my POI before was off by 12" to the right. Took the gun home to recheck against the laser - laser dot is still centered above the front iron and the red dot is still aligned with the laser.(?) I think I can eliminate the red dot not holding zero at this point - laser/red dot/irons are all the same before and after zeroing and live fire. Was looking at the rifle scratching my head and noticed this - seems that the barrel is canted to the right checking against the handguard.

So what I think I’ve figured out:
-Laser sighter seems to be true - no variation when rotated in 90º increments in the bore checked against the red dot and iron sights zero.
-Red dot is holding zero - shots were WAY off of POA but was still aligned to front iron and to the laser after live firing.
Thinking it has to be something with the gun itself - the barrel being off to the right & having to adjust the rear iron far left makes sense. What doesn’t is the POI being low and left to the POA
If anyone sees anything I’ve overlooked, or holes in my theory, please feel free to let me know. Might be time to see the gunsmith.

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the hole that I see is you have the rear sight way to the left and your POI is way to the left. Boresighters are to get on paper, nothing more. Adjust at the range so your favorite round is hitting zero at your favorite distance. I wouldn’t worry about the handguard or the laser.
In theory what you are doing with the bore laser is correct.
Someone once said:
“In theory, theory and practice are the same. In practice they seldom are”.

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Only one thing remaining I can think of.

The laser unit may be properly centered in it’s own cartridge, which your rotation test seems to confirm. If there’s slop in how the laser fits in the chamber, then rotating it would not reveal that. You would get the same reading no matter what.

Too large a gap (headspace) between the Sightmark casing and walls of the chamber would assure your laser’s POI is going to be off. There’s always headspace in a firearm. A cartridge would get stuck otherwise. But it is very small. Most in-chamber lasers don’t use real ammo brass cases. It’s a fake case. Could be the OD of the laser is too small. Thus, too much headspace. You could check this if you have a really good micrometer.

It’s possible your upper and lower fit may be too sloppy. But that’s easy to spot visually and simple to prove or dismiss. I’m going to stick with the laser being the most likely offender.

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