zeroing in a new red dot. I need assistance

[freeeire1916]

Hey Guys,

Based on insight from some of you , I have bought a red dot sight I could afford (bushnell trophy sight model 73-0134) for my AR15. I was also able to figure out how to fit it on without interfering with my magpul BUIS. Yesterday, I took it to the range in an attempted to zero it. Based on most web sites and the instructions in the box, I shot it from 100yrs. The problem I ran into is I can't see where im hitting when I shoot from that distance. At the range I am not able to take three shots and walk to my target.

I guess the question is how does everyone else do it? If I go to Target master I can bring the target to me when I take my shots but Its only a 25 yrd range. Can a red dot be sighted in from that distance? If it can be done, how and will it effect how accurate it is at 50yrs or 100yrs?

[Guns4Fun]

It is my opinion that the 50yd zero is the best for an AR.

By zeroing in at 50yds, you will be about 1.5 - 2" low at 25y. 2-3" high at 100y. and back to zero at 200. So, pretty much "on" from 0 - 200yd.

As for not being able to see where you are hitting the target, buy a spotting scope.



EDIT - oops, forgot your other question.

Zeroing at 25yds will produce these results - (or close to them)

At 50yds you'd be about 3" high. at 100yds about 6" high. At 200yds about 10" high.

I am only going by the different calculators i've seen. I have no first hand with the 25y zero because i do not use it.

The 50y zero i gave you above are my own "results" from my own AR's.

[freeeire1916]

Thanks Guns...,

I appreciate the input. Im gonna give it a shot (no pun intended). The outdoor ranges are few and far between where i am located so this project will have to hold off a few weeks.

Thanks again!

[aubie515]

Any optic you just mount, you should sight in at 25yards first to get on the paper. Especially if you mounted the optics yourself. You can remove the bolt, and eyeball the optic and bore, to see if both are on the paper. If you do not have a bore sighter.

[ar15jules]

Any optic you just mount, you should sight in at 25yards first to get on the paper. Especially if you mounted the optics yourself. You can remove the bolt, and eyeball the optic and bore, to see if both are on the paper. If you do not have a bore sighter.

Yep, what he said.
Jules

[Andrew17019]

Any optic you just mount, you should sight in at 25yards first to get on the paper. Especially if you mounted the optics yourself. You can remove the bolt, and eyeball the optic and bore, to see if both are on the paper. If you do not have a bore sighter.

+1

I also agree that an AR with a red dot is best suited for < 50 yds. Depending on how you want to shoot it, though, I often reach out to 2-300 for man sized targets, but it's more fun shooting at < 100 because you can see results.

[thirtyonebravo]

As mentioned, start from a closer range first, but I'd like to second the mention of a bore sight; they're cheap and very helpful.

[freeeire1916]

wow lots of input!

I did mount the sight myself and just used my eyes to line things up. Took it the the range and sent 30 rounds from 100yrd with all holes accounted for on the paper. (Using a zeroing target.)

At 100yrds, all of my shots were anywhere from 1 to 7inches high from the bulls eye; however, Not a single bullet hit below the line for the lower half of the target. I figured it was because I was sitting, and perhaps i was shooting on an upward angle. I dropped my aim, by my account, approx 3 inches. All shots were once again on paper but a few were actually dead center bulls eye(no doubt by chance) and spread to all sectors of the target. For the most part all were on the target area with only a few hitting white no mans land.

Going back to the first reply of this tread. If the numbers given are accurate. If I sight the dot on a 25yrd target and aim dead center and set the dot so that it hits 2 inches low, wouldnt that in fact set me up for dead center at 50yrs?

[ForwardAssist]

What I do is pull both pins and detach the upper. Then I bench rest it and use the Mark I eyeball to sight through the bore and align it with a fixed object a comfortable distance away. A door knob inside your house works very well. An AR's front sight height is 2.5" above bore centerline. Mark a spot on the wall 2.5" above the door knob's centerline and adjust your red dot to zero on that mark. This will get you on the paper at 25m, a few clicks low.

As the other guys mentioned, I like a 50m zero myself. At the range you can begin dialing it in at 25m. Just make adjustments to place the point of impact around an 1.1 inches lower that point of aim at 25m and she'll be close.

I recommend Kyle Lamb's book, "Green Eyes, Black Rifles". It's got some good information in it such as ballistics charts.

[aubie515]

I am too lazy to research what the MOA dot size that Bushnell uses on their red dot. The dot size along with ammo weight will factor into those "ballistic tables" that were mentioned earlier. Since most AR15 owners typically shoot some sort of 55gr bullet, I'll assume that's what the OP is using.

To the OP, instead of trying to zero at 100 yards, I think you need to take a training course. You seem a bit new around firearms. Save your ammo and start practicing at 50 & 75 yards.