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View Full Version : Ideal distance for zeroing your rifle scope


Crowesnest
04-08-2011, 10:07 PM
I guess it's really all about preference, but at what range (25, 50, 75, 100 yards?) do you all zero your rifles/scopes? For me, I live in a ghetto neighborhood, so it's all about home perimeter defense and when the SHTF. I was looking at 50 yards, but that's 150 feet...quite a distance. I have an AR style rifle with a 16" barrel and 1:9 twist. I will be zeroing using my Eotech XPS with 3x magnifier. Your advice would be most welcome.

AlliedArmory
04-08-2011, 10:16 PM
Well, HD and range shooting is different. I personally think a 50yrd zero is ideal for any red dot.

ArmedDefense
04-08-2011, 10:18 PM
Definitely not an expert, but I'd say pick a good medium so that you have room to adjust for range, either closer or further away. For example, when would you transition from your handgun to your rifle? 25/50 yards? I would put that point at the distance you are most comfortable from your red dot, based on the fact there aren't any reference marks, and then find the yardage at which your dot is right on. Or you can work the other way, and set your dot at say 75 yards and then, with practice, learn at what distance from the dot equates to accuracy of your rifle at said distance. Just a thought...

palakaboy
04-08-2011, 10:21 PM
Well, HD and range shooting is different. I personally think a 50yrd zero is ideal for any red dot.


this.

XDshooter
04-08-2011, 10:53 PM
A good zero for red dots or irons is one that can get you hitting close and far around zero.

With 223 it usually means getting a 200yrd zero and with that is some other closer zero around 35 yrds or so. This all depends on the round and the rifle.

100yrd zero is worthless in my opinion, because a 200yrd target will have way too much drop.

A 35/200yrd zero will get you hitting an 8" target out to 250yrds without using hold overs.

The best zeros are ones that put you closer on target within the range you plan on hitting without using any sort of hold over.

dieselpower
04-08-2011, 10:54 PM
Ok forget the 3X, its for distance and you will only need that past the city block you will be defending. I wouldn't even have it installed until I got into an area where my threats were greater than 150 yards.

The school of thought you need is to understand the pros and cons of each zero and adjust your zero when needed.

lets take a common 55gr ammo...heres that stolen chart of mine.
http://i655.photobucket.com/albums/uu272/Wiringguy/Zerobulletpaths.jpg

The 25 yrd zero.
High arc. cross zero at about 375 yards
threats closer cause the POI to be above the POA, the max is at 225 yrds and is 10" high. Using an EOTech viewing a man sized threat at 225 yards means a 6 foot man will fit from the center dot to the ring (65" as viewed @ over 200 yards) So you now know the POI will be SLIGHTLY above the dot. Place the dot on the lower chest, pull the trigger POI will be high chest. MOA of a 16" 1:9 firing 55gr is 1MOA so you have a 2" error already. Thats 12" if you are 100% steady. Myself I would be placing my dot just above the man berries and my POI will be center mass chest. EOTechs excel at this zero. At farther ranges near 400 yards. Man sized threats fit well inside the 65MOA ring, so your dot gets placed on the chest area. Once again your MOA on the rifle is 4inches. You can expect to hit a chest area @ 400 yards. Closer ranges the 65MOA = 65 inches @ 100 yards = 5.4 ft tall. So if a man fits inside the 65 MOA ring he is basically 100 yards away, look at the chart. @ 100 yards a 25 yard zero gives a POI 5 inches high. Place the dot on the chest and pull the trigger...you are going to hit the chest. Even with a 1MOA error that is 6 inches, which is a center man boob if you fire at center mass chest. (not high chest..please remember CM = sternum, NOT man cleavage).

Therefore the best URBAN zero for an EOtech is 25 yards.

Once you move out side the city and into major ranges the 25 yrd zero + EOtech help you engage threats at greater range. Look at the chart.

Your target threat is 500 yards, (the max I would expect a 55gr projectile to critically wound a man..infact I wouldn't even go 500 yards, but since we know have a 3x installed I can walk my shots into critical soft tissue.) Extending the chart line to 500 yards shows a -20 inch drop. Your man sized threat is 1/4 sized inside the 65MOA circle. By placing the dot just above the head, the projectile should POI the chest. The MOA error is at least 5 Inches. So with a rest, good technique, good followup shot walking and 3X you should be hitting that center mass easy.

just my 2 pennies. Others may say 50yard zero... which means you have a flat trajectory out to 250 yards, but past that the EOTech reticule does nothing for you. I think a shooter who uses a single Dot like an Aimpoint or C-more needs a 50 yards zero since he has no reference beyond what he thinks the range is. He needs to take advantage of the projectile flat trajectory and guesstimate with hold over allowing the round to drop into the target @ as close of ranges as 300 yards. Now a 2MOA dot covers 6inches @ 300 yards, so holding the dot on the face drops the round into the chest....but thats nothing to do with an EOTech which has a 1/3 MOA dot and is seen as a 1MOA dot by the human eye.

just as an example a 400 yard target using a 50 yard zero. The MOA of the EOTech is 16 feet from the dot to the circle. The projectile drop is like 2 feet...how are you going to gage that? With a larger dot size I can give a good guess or use my BUIS. With an EOtech set with a 25 yards zero I don't have to use my BUIS...my center dot is nearly 100% on target.

CK_32
04-08-2011, 10:56 PM
Id zero at 25 yards for that long distance 100.

DRM6000
04-08-2011, 11:21 PM
go with the 50y/200y zero. you'll only be high or low about 1.5" from like 5yds out to 200yds. just remember to compensate up to about 25yds if you need a precision shot are behind cover or concealment.

dieselpower
04-08-2011, 11:40 PM
Just remember if you use the 50 yard zero you are dropping rounds into your target past 200 yards. If you have the bullet drop dots on your EOTech you can align them as needed. If not its a guess.

If you are not going to EVER use the 3x sell it. It doesn't do you much good with a 50, 75, or 100 yard zero. You can see the target better but you are just holding the dot over the target and dropping rounds into them...total guess.

Really the 25 yards zero works best with a 3x. You get the best of both worlds. Without the 3X your point of impact is a little higher. As the target range increases and you need to use the 3X, the center dot again becomes the zero. Its a win win.... and is what the EOtech reticule & magnification does best.

RDS+magnifer = 25 yard zero
RDS alone = 50 yard zero (2MOA dot)
RDS with a 4MOA dot = 75 yard zero

Crowesnest
04-09-2011, 5:20 AM
Thanks for the replies.... With the 3X, I think I will go with the 25 yard sight in.

only10x
04-09-2011, 5:53 AM
interesting chart Diesel

Don29palms
04-09-2011, 6:27 AM
I have mine sighted in at 50yds. I regularly shoot steel targets at the range out to 500yds.

PlacerTactical
04-09-2011, 6:52 AM
I normally zero at 50 but Diesel makes a good point on the 25yd. Certainly worth a look into and try.

Fjold
04-09-2011, 7:11 AM
For perimeter home defense, what does it matter? You're talking about man sized targets at probably less than 50 feet. Two inches lower or higher isn't going to make any difference if you're holding center of mass.

CSACANNONEER
04-09-2011, 7:17 AM
Like I have posted in the past, just zero your optics for the distance you plan on shooting. It only takes one shot and one quick adjustment to properly zero optics at any distance.

dieselpower
04-09-2011, 10:59 AM
For perimeter home defense, what does it matter? You're talking about man sized targets at probably less than 50 feet. Two inches lower or higher isn't going to make any difference if you're holding center of mass.

+1 Lots of logic here. The real action starts at ranged threats. The same logic holds true with respect to a few inches as seen by the reticule size as compared to the target size.

Its only when you add a Magnifier to an RDS where the 25 yard zero surpasses the 50 and 75 yard zero. Its much simpler to aim with your center dot, then hold over and drop rounds into the target.

When that target starts moving behind cover...the value/benefits of an accurate center dot aiming point becomes apparent.


Like I have posted in the past, just zero your optics for the distance you plan on shooting. It only takes one shot and one quick adjustment to properly zero optics at any distance.

Very true. Which is why I said to learn the pros and cons of each as it relates to your set up. The only RDS (quality made RDS) that you can not adjust on the fly is the C-More. Once zeroed you can not quickly change it. You must understand what it does as its set zero.

This is why I use a C-More. Its easier and quicker for me to adjust my fire, then adjust my optic. YMMV

PRE-EMPTIVE STRIKE
04-09-2011, 11:49 PM
Are you really using this for HD? If so, at what range do you actually and realistically think you'd have to use it? I've just always been amazed at all the talk regarding what I call "fantasy shootouts". While anything is possible, who would need to shoot past 25yds before it becomes an unlawful shooting instead of self defense? It's always a good thing to master your weapon at any distance, as you should, but for that nightmare that may cross your path, will likely happen within 10 to 15ft of you, at which case a handgun or even a shotgun will serve you much better.

Enjoy your ar at the range and get a handgun or shotgun for HD, and if money is an issue then sell your 3x. just sayin

captbilly
04-10-2011, 7:26 PM
The problem with 25 yard zeroing is that it is difficult to accurately see small errors in sighting. A 1/4" error in sighting at 25 yards will result in 4" error at 400 yards, but if you sight in at 200 yards you will find it much easier to tell if you are off by even 1/4 MOA (1/2" at 200 yards). If you look at the chart presented by another poster you see that if you zero at 200 yards you will not be off target by more then 2.5" anywhere between 0 and 200+ yards. I can't see a realistic scenario in which 2.5" error in aiming would be important in a home defense situation.

rattlesnake_nm
04-10-2011, 7:33 PM
That is an excellent illustration diesel power. 100 seems to be the best zero. Now it is a pain using a 4x, but achievable by starting at a closer distance and moving out. That illustration makes it a no brainer that 100 is the best zero.

pyromensch
04-10-2011, 7:36 PM
Ok forget the 3X, its for distance and you will only need that past the city block you will be defending. I wouldn't even have it installed until I got into an area where my threats were greater than 150 yards.

The school of thought you need is to understand the pros and cons of each zero and adjust your zero when needed.

lets take a common 55gr ammo...heres that stolen chart of mine.
http://i655.photobucket.com/albums/uu272/Wiringguy/Zerobulletpaths.jpg

The 25 yrd zero.
High arc. cross zero at about 375 yards
threats closer cause the POI to be above the POA, the max is at 225 yrds and is 10" high. Using an EOTech viewing a man sized threat at 225 yards means a 6 foot man will fit from the center dot to the ring (65" as viewed @ over 200 yards) So you now know the POI will be SLIGHTLY above the dot. Place the dot on the lower chest, pull the trigger POI will be high chest. MOA of a 16" 1:9 firing 55gr is 1MOA so you have a 2" error already. Thats 12" if you are 100% steady. Myself I would be placing my dot just above the man berries and my POI will be center mass chest. EOTechs excel at this zero. At farther ranges near 400 yards. Man sized threats fit well inside the 65MOA ring, so your dot gets placed on the chest area. Once again your MOA on the rifle is 4inches. You can expect to hit a chest area @ 400 yards. Closer ranges the 65MOA = 65 inches @ 100 yards = 5.4 ft tall. So if a man fits inside the 65 MOA ring he is basically 100 yards away, look at the chart. @ 100 yards a 25 yard zero gives a POI 5 inches high. Place the dot on the chest and pull the trigger...you are going to hit the chest. Even with a 1MOA error that is 6 inches, which is a center man boob if you fire at center mass chest. (not high chest..please remember CM = sternum, NOT man cleavage).

Therefore the best URBAN zero for an EOtech is 25 yards.

Once you move out side the city and into major ranges the 25 yrd zero + EOtech help you engage threats at greater range. Look at the chart.

Your target threat is 500 yards, (the max I would expect a 55gr projectile to critically wound a man..infact I wouldn't even go 500 yards, but since we know have a 3x installed I can walk my shots into critical soft tissue.) Extending the chart line to 500 yards shows a -20 inch drop. Your man sized threat is 1/4 sized inside the 65MOA circle. By placing the dot just above the head, the projectile should POI the chest. The MOA error is at least 5 Inches. So with a rest, good technique, good followup shot walking and 3X you should be hitting that center mass easy.

just my 2 pennies. Others may say 50yard zero... which means you have a flat trajectory out to 250 yards, but past that the EOTech reticule does nothing for you. I think a shooter who uses a single Dot like an Aimpoint or C-more needs a 50 yards zero since he has no reference beyond what he thinks the range is. He needs to take advantage of the projectile flat trajectory and guesstimate with hold over allowing the round to drop into the target @ as close of ranges as 300 yards. Now a 2MOA dot covers 6inches @ 300 yards, so holding the dot on the face drops the round into the chest....but thats nothing to do with an EOTech which has a 1/3 MOA dot and is seen as a 1MOA dot by the human eye.

just as an example a 400 yard target using a 50 yard zero. The MOA of the EOTech is 16 feet from the dot to the circle. The projectile drop is like 2 feet...how are you going to gage that? With a larger dot size I can give a good guess or use my BUIS. With an EOtech set with a 25 yards zero I don't have to use my BUIS...my center dot is nearly 100% on target.

it shows a 55gr bullet from a 1/7 twist barrel? isn't that a little fast, for that bullet, and might cause irregular results, and out of a 14.5 barrel?

docsmileyface
04-10-2011, 7:58 PM
If its an optic with a BDC reticle, I zero at 100m. Red dot sights I zero at 25m for 300m - force of habit from the Army. Added plus is a 25m zero will cause the round strike the head area if you aim center of mass at 100m :D

dieselpower
04-10-2011, 8:20 PM
If its an optic with a BDC reticle, I zero at 100m. Red dot sights I zero at 25m for 300m - force of habit from the Army. Added plus is a 25m zero will cause the round strike the head area if you aim center of mass at 100m :D

I agree. I tell ya, those of you with Aimpoints and EOtechs with magnifiers need to check out a 25 yard zero.

As for what Rattlesnake said, I like the 75 yard over the 100 for a 4MOA dot, but I can see 100 yards being ok too. The 50 is good and the easiest to zero at. Gets tricky at 75 and 100, but the MOA size of the 4MOA dot aids in bullet drop with a 75yard zero.