Red Dots and Parallax

One of the benefits of the red dot on a pistol is the ability to take advantage of the gun’s inherent accuracy. When red dots became mainstream on rifles in the 90’s, we were all told that the dots were parallax free. Some of us even believed it until our shooting and training became advanced enough to notice that it might not be true. But what about on a pistol? Are they parallax free? Does it matter?

I have been shooting and testing my new LTT P30L for the past week or two, as it is going to be my backup competition pistol. I mounted a 507 Comp on it, rather than my favored SRO, as I wanted to see if the larger window and reticle options might be helpful. Since the optic is new, I decided to test it for parallax. The picture below shows the results.

Three of the four high center shots were shot normally for a base comparison. The remaining four shots were fired with the dot at the extreme edges of the window, up, down, left, and right. Except for the right side, you can plainly see the results of the other holds. The target was shot at 25 yards, and the gun is zeroed at 50 yards, which is why the center group is a bit high.

I then decided to see how the SRO compared, see photo below. The gun used was my main LTT P30L, also shot at 25 yards and with a 50 yard zero.

The next picture is my CZ Shadow 2 with the C&H Precision EDC XL optic, mounted on a C&H plate. I have very little time on the CZ, but it and the optic have impressed me so far. I’ll talk more about it some other time, but as you can see, that C&H optic seems to have the least parallax of the three. It also has the smallest window of the three, but it is still large enough to be very usable. It also has a 25-yard zero, hence the more centered group.

Finally, we have a G45 with a direct milled C&H Comp sight, also zeroed for 25 yards.

A few things should be mentioned before we go further. Shooting like this is not the best way to test parallax. A better way is to clamp the gun down and aim it at a paper with a 1″ grid. Move your head around behind the gun and count how many grid squares the dot will move in each direction. Not easy to show in a post, but very easy to do. I did not do that so I can’t report that data.

How the optic is mounted will affect apparent parallax, so comparing one optic on one plate to another optic on another plate, on another gun, is not apples to apples. In this case the 507Comp and the SRO can be compared since both are on LTT P30L’s. The others are what they are.

For Action Pistol, parallax can certainly matter, which is why I tested it. For any other application that I would use these guns for (carry, duty, USPSA, Steel Challange, IDPA), I don’t think any apparent or actual parallax shown here would matter.

5 comments

  1. Man, this is a great post. And, as always, I learned from it. I’ve never done parallax testing with any of my optics, outside of my sniper rifle setup.
    Also, hurry up with the CZ info drop damnit! Please!!!

  2. Thanks very much! I do want to give the CZ its due, so I can’t say I’m really ready to write about it yet. It is a great shooting gun so far.

    1. I wish you were local to me, I’d lend you some Henning grips for that CZ, they make it so much nicer to grip.

      1. I appreciate the thought, but have to say, the factory grips seem to work very well. Henning better than Lok?

        1. I really tried to like the Lok, and just found them, ick. Henning’s grips are almost the same LPI as the front and back serrations, and even with big hands I find they fit perfect. His checkering covers more of the area of the grip than others, including Lok, and especially the factory ones. Definitely worth giving them a test run if you know someone local who has em.

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