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Discussion Starter · #1 ·
I just bought a short barrel 45-70 and mounted a Vortex Spark red dot sight. My problem is the parallax error. Every time I snap it up to my shoulder the dot is not centred over the front sight as it was when I sighted it in. Am I missing something basic about sighting and using a red dot? I bought the gun for elk hunting in heavier brush here in British Columbia. So far I just don't have the confidence in the red dot to take it hunting.
Maybe a set of XS ghost rings are the answer. Any help or comments would be appreciated.
 

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My first exposure to red dots was an Eotech on my AR15. A retired army buddy of mine explained it to me this way. I can't explain how that dot moves around when you change your eye position but you still hit your target. He was right, it's just weird. I did the same thing to co witness my front sight while the gun was in a vise. Go to shoulder and co witness no longer, aarg.
How did I solve the problem you ask? I gave that gun to my wife, she loves it. I put a regular scope on mine ;-)
My better half just focuses on the dot and really doesn't pay attention to the front sight.
 

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I've never used the sparc but it is supposed to be parallax free. If the dot is on target you will be good to go. I use aimpoint micro's and the dot is not always centered when rapid firing, just keep both eyes open and focus on your target. Definitely the best sight option for quick work IMHO.
 
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Answers are correct... put the dot on the target, breath control and squeeze.

Or..... Skinner Sights... :)
 
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All the members above are correct. I would also like to add that you need to find out what the limit of the parallax cone is at. Aimpoint requires around 50 yards until the dot will track without perfect cheek weld placement. Eotech is parallax free. The most important thing to keep in mind in this process is to either zero beyond the parallax cone or be rally careful about the cheek weld and distance in the zero process. AR-15s are much easier in this respect because the popup sights allow for a co-witness. Having said that, Vortex is Parallax free (good on you for that). Test at 50 yards and then 75 or 100 yards. That will let you know you are tracking correctly. There is no such thing as too much information. Hope all that helps.

-Craig
 
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absolutely agree with everyone here 100%
One more thing you can do that helps, is to move the unit out as far away from your eye as you can, that really helps "stabilize" the dot.
The closer to your eye, the more the dot will appear to drift around and not be centered in the sight.

and definately shoot with both eyes open, looking past / thru the sight, if it is sighted in, no matter where the dot is in the frame, it will hit where the dot is. takes some getting used to.
 

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OS 65,

A little OT but one thing about any battery powered sights is the battery life is reduced by colder weather. This creates a bit of a quandry, leave the sight on all the time so you are ready to shoot, or leave it off to save the battery and maybe there isn't time to turn it on (or worse you forget to turn it on)? I use red dots and EOtechs (clone of course, I am cheap) for plinking and 3-gun shoots but never for hunting. I have had several friends miss oppurtunities on nice whitetails because of a dead battery.

BB
 

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Discussion Starter · #11 ·
Thanks for all the information. I'll move it to the forward position on the rail and sight in at 50 yards then go from there. I do shoot it with both eyes open so hopefully it's just a familiarity thing. It's nice to have a forum like this where you can get so much information that directly relates to the problem.
One solution to batteries dying at inoportune times, I use a Butler Creek sling that has a point at the top of the sling where the elastic is sewn into an expansion loop. The loop is quite tight and just long enough to squeeze a spare battery in. The battery will never fall out and there's always a spare wherever the rifle goes.
After leaving my Spark turned on in the gun cabinet for three weeks I went to the range and found that the sight would not turn off. Problem was a low battery. A nice feature rather than a blank sight window when the battery is low.
 

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A few months back I bought an SBL and put a Leupold DeltaPoint Reflex on it. Havig not much experience with either the large bore rifle or the red dot, I'm having difficulty sighting it in. Anyone have any suggestions? As I don't re-load yet, I've been running Hornaday Leverution through it. Should I do a zero point blank range like I do on my .300 WinMag? If I do, what should I range it at?
Thanks for the help.
 

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All red dot sights, including Eotech, exhibit parallax at distances under about 50 yards. The front sight is perhaps an extreme example, unless you are shooting into ant hills. This type of parallax, due to the focal point of the optics, will cause the dot to move against the subject if you move your eye around. Beyond the focal distance, the dot is steady against the subject, regardless of eye position.

You also get a parallax effect at 50 yards affecting the point of impact. This is due to the height of the sight above the bore axis. It is normal for a red dot zeroed at 100 yards to shoot about 2.5" low at half that distance. If you zero at 50 yards, you will shoot about 5" high at 100. The optical center is typically about 40 mm above the mounting rail for an Eotech, or an AimPoint on 15 mm risers.

If you are zeroed using iron sights high enough to serve as co-witness sights with the red dot sight, the red dot will rest on top of the front blade when you align the target with the iron sights. That's not going to happen on a Marlin, but it's SOP on a "modern sporting rifle."

It doesn't matter where the red dot is mounted on the rail. It's perhaps quicker to visually acquire if it's closer, but less obstructive to two-eye shooting further down barrel. If you mount it forward, there is space to put a magnifier on the receiver, which is great for long range (150 yard plus) shooting, and doesn't affect the POI. I have a 3x Aimpoint, which I move from rifle to rifle as need dictates.
 
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