My first red dot scope - questions

[johncanfield]

Also my first AR build . I did an 80% lower, bought a barreled upper from PSA and put it all together, very satisfying. Anyway I was sighting in the AR at 25 yards this morning and going for 4" high like I usually do when I'm figuring a 100 yard bullseye. Then it dawned on me that with only a red dot (I bought an Aimpoint) there are no holdovers possible. So what to do...

With no magnification I doubt that I could be precise at 100 yards with my old eyes so now I'm wondering why I bought a red dot . What appealed to me was the light weight of the red dots and their holographic cousins and my AR build is a wonderful lightweight so that objective is a complete success.

I'm wondering if maybe I should sight it in for 50 yards and then I can push it out or pull it in a little? Any pearls of wisdom out there?

On another note, I'm going to do another build and thinking about 300AAC Blackout for my other lower.

[txcharvel]

I have a Vortex Strikefire on my AR sighted in at 50 yards. In theory, this should be on at 200 yards as well and never be outside the front sight post from 25 to 300 yards. So far this setup has worked well. I've been tempted to throw a scope with magnification on it, but I think you'll be surprised what you can hit with a red dot. I know I was.

[johncanfield]

I have a Vortex Strikefire on my AR sighted in at 50 yards. In theory, this should be on at 200 yards as well and never be outside the front sight post from 25 to 300 yards...s.

So if you sight in the red dot at 25 yards, 50 yards or whatever, then wherever the dot is that's the point on impact? That would be way cool.

[txcharvel]

If you're sighted in at 50 yards then your point of impact will be where the dot is. Point of impact will be a little low at 25 yards and a little high at 100, but never more than just a few inches (I used the front sight post as a reference but your build may not have one).

Let me also say that I'm no expert, but this setup has worked well for me with targets and hogs.

[johncanfield]

Fantastic, thanks for helping a newbie. I think what I'll do is sight it in at 25 yards and then see what I get at 50 and 100 yards.

[Pawpaw]

Fantastic, thanks for helping a newbie. I think what I'll do is sight it in at 25 yards and then see what I get at 50 and 100 yards.

This is in meters, but yards would still be "close":

[lfinsr]

Kind of the teach a man to fish thought process...

Strelok is a free ballistics calculator that can be used to make a determination of how you would like to sight in your optics, or red dot in your case. Plug in the numbers and see for yourself. If you don't have an Android phone there are online calculators also. Obviously it helps if you have velocity numbers for the ammo you're shooting but it's available for many common commercial loads.

After finally getting my hand loads where I want them I find that out of my 18" AR if I sight it in at 50 yds., it's good to ± 2" from 0-220 yds. Point and shoot.

Larry

[johncanfield]

Thanks fellows! I'm sort of familiar with ballistics, I use Strelock and Mildot master when I do long range shooting. About a month ago I was hitting steel plates at 500 yards with my .308 Bushmaster . My question in this thread is really about how the red dot works in practice. If I sight it in at 25 yards or meters, will I be about 4" high at 100 yards, if so how do figure holdover with no reticle?

[Pawpaw]

Thanks fellows! I'm sort of familiar with ballistics, I use Strelock and Mildot master when I do long range shooting. About a month ago I was hitting steel plates at 500 yards with my .308 Bushmaster . My question in this thread is really about how the red dot works in practice. If I sight it in at 25 yards or meters, will I be about 4" high at 100 yards, if so how do figure holdover with no reticle?

Actually, you will be closer to 6 inches high at 100 yards. Look at the chart I posted. If you sight in at 50 yards, your bullet strike comes in at no more than 2" high or low all the way out to 250 yards.

Hitting within 2" of POA is a good kill shot on everything but the smallest game.

[PBR]

there are several nice magnifiers out now days that will let you see out to 100 yds easy -- and with flip to side bracket you can flip it out of the way when sighting in much closer distances

[johncanfield]

Roger on the magnifier, noticed they are available. I guess I'm still not making my dilemma clear. What I think I know so far is:

The red dot is like any other shooting optic
If you sight it in at what ever distance, the bullet will obey the trajectory table
There is no magic in the red dot optic that compensates for drop

The question remains how do most people use their red dot scope? Sight it in at 50 yards and call it good enough for anything between 25-100 yards since there is no reticle and you can't calculate holdovers?

[lfinsr]

Roger on the magnifier, noticed they are available. I guess I'm still not making my dilemma clear. What I think I know so far is:

The red dot is like any other shooting optic
If you sight it in at what ever distance, the bullet will obey the trajectory table
There is no magic in the red dot optic that compensates for drop

The question remains how do most people use their red dot scope? Sight it in at 50 yards and call it good enough for anything between 25-100 yards since there is no reticle and you can't calculate holdovers?

You're trying to figure out holdover and we're trying to eliminate it from the equation.

Personally, if I have mine sighted in as everyone explained, I can point and shoot from point blank to over 200 yds. and hit within a 4" circle. Anything over that and I have the wrong firearm/optics combination. That's the method I use, YMMV.

I think most will agree that a red dot is not ideal for long range shooting. The only method you could use would be to estimate the holdover distance on the target but you would have no means to do so precisely without a reticle. Either way it still requires that you know the ballistic profile of the chosen ammo.

[PBR]

Roger on the magnifier, noticed they are available. I guess I'm still not making my dilemma clear. What I think I know so far is:

The red dot is like any other shooting optic
If you sight it in at what ever distance, the bullet will obey the trajectory table
There is no magic in the red dot optic that compensates for drop

The question remains how do most people use their red dot scope? Sight it in at 50 yards and call it good enough for anything between 25-100 yards since there is no reticle and you can't calculate holdovers?

yea i see what your asking now -- pretty much like others said just sight it in for 50 yrds and basically 25 to 200 you will hit within a 4in area -- maybe not a bullseye every time but on anything of size it will be a kill shot -- correct on no compensates for drop using red dot if shooting out past 200 yds you cant see a target that size anyway even with magnifier -- basically the dot will be the size of a normal person's complete top torso or more so it's not like you can zero in on a heart or head shot at that distance

[Pawpaw]

Roger on the magnifier, noticed they are available. I guess I'm still not making my dilemma clear. What I think I know so far is:

The red dot is like any other shooting optic
If you sight it in at what ever distance, the bullet will obey the trajectory table
There is no magic in the red dot optic that compensates for drop

The question remains how do most people use their red dot scope? Sight it in at 50 yards and call it good enough for anything between 25-100 yards since there is no reticle and you can't calculate holdovers?

Exactly. A red dot scope is a SPEED sight, not a PRECISION sight. The dot itself is the first clue. Your dot is most likely 3 or 4 MOA, possibly larger. You're not going to be able to use it to shoot sub-MOA groups at any range.

[The Annoyed Man]

Roger on the magnifier, noticed they are available. I guess I'm still not making my dilemma clear. What I think I know so far is:

The red dot is like any other shooting optic
If you sight it in at what ever distance, the bullet will obey the trajectory table
There is no magic in the red dot optic that compensates for drop

The question remains how do most people use their red dot scope? Sight it in at 50 yards and call it good enough for anything between 25-100 yards since there is no reticle and you can't calculate holdovers?

Exactly. A red dot scope is a SPEED sight, not a PRECISION sight. The dot itself is the first clue. Your dot is most likely 3 or 4 MOA, possibly larger. You're not going to be able to use it to shoot sub-MOA groups at any range.

+1

I just took delivery on a new Aimpoint T2 Micro with a 2 MOA dot a week ago. Even with a small dot like that, and assuming I can even see the target at that distance, that means that dot covers a 2" circle at 100 yards......a 4" circle at 200 yards.....and a 6" circle at 300 yards. With a 4 MOA dot, double those circle sizes at each distance. These are not "precision" sights. However, if your sight is zeroed for the right distance, they become a true point and click interface. A 50 yard zero for a red dot sight with no bullet drop compensating reticle (or at least, no appreciable bullet drop compensating reticle) is about perfect for a shooter of average skills out to 300 yards. Eagle eyes can do even better. I can't any longer. My eyes require magnification to shoot anymore. But I'm pretty sure I could hit a man-sized target at 200 with a red dot, and further than that with a magnifier lined up behind it. That said, you'll never shoot dime sized groups with an RDS.

........and BTW, if your AR15 shoots 2 MOA groups, and your sight has a 4 MOA dot, you can't even see the bullet strikes at the zero range. 2 MOA at 50 yards is a 1" group, which would be totally obscured by the 2" area covered at 50 yards by a 4 MOA dot.