Zeroing distance for Irons/RDS

[muddywings]

I thought I would put this in here vs GD since I'm gearing this question for various competitions.
What are peoples thoughts for zeroing Ar-15 irons/RDS (Aimpoint M2) sights?
I did have it zero-ed for 100 yards since that is as far as i could shoot from my super secret Rampart Range Road range. But with the Cheyenne Mountain Range at Carson opening up I was thinking about 300 yards. Reading some other sights and see Haley's visual: http://www.youtube.com/watch?v=YUwve2VMFBU makes me initially agree with what I was told via another site-the further you can zero the better. I also like the hold overs for 300.
I have never shot irons (for accuracy) out to 300 so I don't know how unrealistic I am being. I was thinking I would use black electrical tape to make a cross on the target to help with get the same sight picture off of the front sight. I guessing the target is going to be pretty blurry at that distance.
Thoughts and/or advice?

In the same breath, with a 3x9 scope, what do people zero those at? Again, currently zero-ed for 100.

Thanks

[Delfuego]

Leave it at 100y. Learn your hold-overs and hold-unders for different ranges. You may also look into a calibrated BUIS like the Matech or Knight's rear sights. These will give you the ability to quickly adjust your irons for different distances without losing you 100y zero. Good luck!

Should be in this forum: http://www.ar-15.co/forums/100-Sights-Optics-and-Zeroing

[ray1970]

I zero mine for 25 yards. Puts it about 3" high at 100 yards and dead on again at about 300 yards.

So I can basically just hold dead on all the way out to 300 yards and get good center mass hits.

[muddywings]

thanks...my bad...totally forgot about that one.

[Hoser]

I zero irons at 200 and optics at 300.

[FireMoth]

We actually run a 50/200 zero now.

The 300yrd zero gives you a smaller cone of deviation, but puts your rounds at the knees at 400.

The result of that is at 400 yards you have a hold over that blocks target image with iron sights.

The 50/200 opens up the cone of deviation to about 9 inches (nearly triple the 300 yrd), but is still combat effective, and puts 400 center hold hits in the groin area. That means at 400, if i hold head, im hitting center mass. Longer engagement range.

Between the two, ask yourself how small a target you are engaging, and how well you can see. Some people literally cant see a man at 400 well enough to engage, so that would be wasted.

[mtnrider]

I watched Haley's video's also and was curious about the 300 yard zero. I might have to give it a try myself. My question is my optic is the M2 with the 4MOA dot so is it realistic for me to try to zero at 300 with that?

,

[CO-Exprs]

In general I like a 300yd zero for RDS and I use Matech for the rear with a 300yd dead zero when set at 300yds. This gives me 25yd cross over for close fast stuff and only slight variation in holds out to 350. At 400 aim at the head for COM hits. At 500 you hold about 3ft high (or half a man). Easy peasy. I sometimes use a 200yd zero, such as at the upcoming CO state multigun championship in April. Longest shots will be 200 and most berms are 50yds. 50/200 will be perfect there.

[CO-Exprs]

Yeah, it won't be perfect, but if you wanted parfect you would have gone different on the glass. It still works. Any more... I'm lazy and just sight in on steel down at Pueblo. I don't often put up paper any more.

[mtnrider]

Yeah, it won't be perfect, but if you wanted parfect you would have gone different on the glass.

Well I got a couple of M2's dirt cheap so that's what I went with. Wasn't my first choice but I couldn't pass them up at the price I got them. Eventually want to get a T1 (or something) with the 2 MOA.

[Kaiser.Shooter]

We actually run a 50/200 zero now.

The 300yrd zero gives you a smaller cone of deviation, but puts your rounds at the knees at 400.

The result of that is at 400 yards you have a hold over that blocks target image with iron sights.

The 50/200 opens up the cone of deviation to about 9 inches (nearly triple the 300 yrd), but is still combat effective, and puts 400 center hold hits in the groin area. That means at 400, if i hold head, im hitting center mass. Longer engagement range.

Between the two, ask yourself how small a target you are engaging, and how well you can see. Some people literally cant see a man at 400 well enough to engage, so that would be wasted.

this ^^^ my vote 50/200 zero

[DocMedic]

It has been said, its really match specific, but after talking to a bunch of Iron Sight / 1x 3gun shooters around the country the general conciseness is to use a 300 yard zero, that way you only need to hold under for everything else thats closer (easier to hold under then over with irons). I can't remember off hand but 66yard depending length of barrel and ammo used will put you close to a 300yard zero, this will help you save some time adjusting and you can always fine tune on the 300yard mark. Also when you get your zero, pull it off the table and try to shoot it offhand, prone unsupported, sitting, and knelling you'll find that sometimes you'll "lose" your zero and thast because your head while zeroing is more relaxed and slumped over on your buttstock, when in other positions (specially in competition) we have a tendency to stiffen our heads causing a different sight picture. causing what we believe is loss of zero (nose to charging handle anyone :o) It less noticeable with scopes but a PITA with Irons and Reddots.

[DocMedic]

Heres what one person that shoots irons use to zero at 300yards and explains how he does it.

http://i90.photobucket.com/albums/k274/DyNo541/d4aab867.jpg
http://i90.photobucket.com/albums/k274/DyNo541/55c0d6fb.png