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checkmyswag
September 15, 2012, 09:30 PM
Looking to put some sort of optic on an AR.

Removable carry handle, fixed front sight post.

I want to leave the front sight post so please don't suggest I switch it out.

I am looking at the following options.

Option 1. Typical red dot setup on flat top, co-witness w front sight

Question 1. How far can I expect to be able to shoot accurately with a red dot (Vortex Strikefire or similar)?
With iron sights, I'm a decent shot out to 300 meters.

Option 2. 3X or 4X scope (Nikon AR M223 or similar) on flat top, set for proper eye relief

Question 2. I read some guys saying the front sight disappears at 1.5X, others at 4X. What determines when the FSP disappears? The distance between the optic and the FSP? The objective size? It must be something more than simply the power of the scope in order to cause such a variety of answers.

Option 3. Mount a scope (3x9 or similar) on the carry handle.

Question 3. This seems to be met with near universal disdain. Are there any setups like this that do work well? I hear everyone talk about cheek weld being poor, but I looked at an ACOG carry handle mounted setup and I liked it.

I'm sure I'm missing some option I've considered but these seem to be the main ones. I know many of you will question what I want to do with the rifle, well that's what I'm trying to figure out, what I can set it up to do well and not try to make it fit something else.

Thanks for the input as always.

big al hunter
September 16, 2012, 12:14 AM
Lots to think about.
First option: accuracy will depend on the size of the dot. The vortex strikefire has a 4 moa dot. The dot covers a little more than 4 inches at 100 yds, and more than 12 inches at 300 yrds. So if you already have better groups than 12 inches at 300 yds accuracy will not be as easy with the red dot scopes. There are smaller dots and adjustable dots on the market. That would be my first choice for an AR, and probably will be when I talk my wife into letting me get one without including a divorce. Target acquisition is fastest with a red dot on my handguns. I have been told it is the same for rifles.
Option 2: also my second choice for AR rifles. If long range accuracy is the need, this is the tool for the job. The fsp disapears from view because the magnification changes the diameter of the viewing window. Kind of like the pupil of your eye can get bigger or smaller with light. As you increase magnification the field of view at any distance shrinks. The field of view will also be different with larger or smaller objective lens size. A smaller objective will loose sight of the front post at lower power than a larger objective lens. Which is why you hear different magnification causing the post to disappear. Short answer is it depends on the scope.
Option 3 looks horrible to me. Cheek weld is part of accurate shooting, you won't know how much that set up will change your shooting until you try it.
Have you considered a scout scope or pistol scope mounted further out (do you have a rail or the standard forestock) might not work?

Hope this helps, felt like I was rambling a bit.

Crow Hunter
September 16, 2012, 09:34 AM
Looking to put some sort of optic on an AR.

Removable carry handle, fixed front sight post.

I want to leave the front sight post so please don't suggest I switch it out.

I am looking at the following options.

Option 1. Typical red dot setup on flat top, co-witness w front sight

Question 1. How far can I expect to be able to shoot accurately with a red dot (Vortex Strikefire or similar)?

With iron sights, I'm a decent shot out to 300 meters.

RDS sights are like magic iron sights that don't require you to light up a front and a rear. You just put the dot on the target. Whatever you can do with iron sights you can do with a RDS but now you can do it at night/low light and from weird positions and on quickly moving targets easier than you can with iron sights.

Option 2. 3X or 4X scope (Nikon AR M223 or similar) on flat top, set for proper eye relief

Question 2. I read some guys saying the front sight disappears at 1.5X, others at 4X. What determines when the FSP disappears? The distance between the optic and the FSP? The objective size? It must be something more than simply the power of the scope in order to cause such a variety of answers.

Where the front sight "disappears" depends on the point in space where the focal point of the lenses are. The higher the magnification the further forward that point is. It also depends on where the objective of the optic is and how close you put your eye to the optic.

http://en.wikipedia.org/wiki/Focal_length

This can vary between optics brands and types. Honestly you will have to try it for yourself. I have tried it with a Trijicon TR24 and a TA33 and both of them had a visible FSB to the point that it annoyed me. The TA33 did not have one visible if I shot the rifle nose to charging handle. (But I find shooting like that uncomfortable)

Option 3. Mount a scope (3x9 or similar) on the carry handle.

Question 3. This seems to be met with near universal disdain. Are there any setups like this that do work well? I hear everyone talk about cheek weld being poor, but I looked at an ACOG carry handle mounted setup and I liked it.

I tried this one time. I set it up to mimic a Colt Delta H-Bar like Sarah Connor used in Terminator 2 because I thought it was cool. I WAS NOT cool to use. It was hard to get to the charging handle, you couldn't use the iron sights in the see through mount because the Delta cheek piece got in the way. The offset to the bore was so high that it was something like 6-8" under POA at close range with a 50m zero. (I don't remember for sure, I know it was off the target I was using when I moved up close after I zeroed it.) I used it only one time. I took it all off the rifle when I got it back home, it was terrible.

I'm sure I'm missing some option I've considered but these seem to be the main ones. I know many of you will question what I want to do with the rifle, well that's what I'm trying to figure out, what I can set it up to do well and not try to make it fit something else.

Thanks for the input as always.

Personally, for my shooting, and my anticipated emergency use and hunting use of the rifle, I prefer the RDS. It is a great reactive optic. Very quick and easy to make shots at 200 yards and in, good at night and low light, I don't have to worry about eye relief or cheek weld, very good for making shots on moving coyotes as I usually make the "anchor shot" when I go coyote hunting with my friends and they miss.:D

But it doesn't make a good target sight or hunting optic for very small critters where I am doing "ambush" type shooting. For those types of shots, I prefer a magnified optic. So I would make the decision based on the type of shooting I was doing.

Reactive/defensive shooting and practice - RDS

Ambush/target/hunting shooting and practice - Magnified optic

Then I would try to figure out a way to work/train around the FSB if needed.

bman940
September 16, 2012, 10:57 AM
I'm with Crow on what he described the uses for your rifle. Do you want quick target acquisition or punch little holes in paper or coyote's at long range? I have Nikon's M-223 1-4 Point Blank Reticle on one of my rifles and it work's great for it's intended uses. I like to shoot steel inside of 200 yards while being timed. As soon as I am on target a round is sent. That being said, If I was going coyote hunting and thought my shot's would be further then 200 yards I'd have a scope with more magnification. Right tool for the right job as they always say. Most guy's want to multipurpose which I agree with as well and then a compromise is in order. Not the best of both worlds but lots of fun.

DPMS .223 with Nikon M-223 1-4 Point Blank Reticle

http://i1216.photobucket.com/albums/dd363/bman940/KathyARPBR.jpg

checkmyswag
September 16, 2012, 07:44 PM
Looking at red dot vs 1-4x scope.

That Nikon is one of the exact models im considering.

Vortex strikefire vs Nikon/Burris 1-4x. Not sure what would be best for me but am dropping the carry handle mount on the advice received.

Watch your lane.

Justice06RR
September 16, 2012, 10:39 PM
The best balance IMO is a 1-4x RDS or ACOG-type scope. You still have the capability of magnification, but also the benefit of close range shooting. I'm not sure about your budget, but Trijicon ACOG's are the best in the business although they are pricey. I'm sure there are many other brands out there (i'm not too familiar with all of them) so just look around. The key thing is whatever you get to make sure you have a true 1X on the low end. Some 1-4x optics I heard are not true 1X, but more like 1.5X. Something to keep in mind if you go with a lower end brand.

The 3-9x Scope is another good 2nd option, but remove the carry handle and mount it directly on the rail with the proper scope mount. With the 3-9x scope the FSP will disappear. I have a nice Bushnell Banner 3-9x and I don't see the front A2 sight even at the lowest magnification. This is a great choice if you add a low-profile rear BUIS like Magpul. Just remember that 3-9x scopes are usually long, but I don't mind it with my AR. Plus you can always change/remove it if needed.

In the end, You really need to figure out what you like the most and what best fits your purposes. Most setups allow you to do more than one, but IMO a plain RDS will be hard to use on long-range shots over 100yards. For long range shooting, I always swap out my RDS with a 6x32 or 3-9x40 Scope. (I have multiple scopes so its easy to swap them out based on your needs).

Justice06RR
September 16, 2012, 10:47 PM
To add to Question 3, I'm not sure why a 3-9x is met with disdain. I have experienced this too; my roomate who is a LEO/former Marine says its too long for an AR.

It really doesn't matter as long as it fits your needs. Nothing wrong with a high-magnification scope if you are using it for long range shooting or if you just have bad eyes. It still looks really cool IMO.

jmr40
September 17, 2012, 01:49 AM
I have 3 AR's set up differently.

One has a Nikon Monarch 2-8X standard size scope in QD mounts for longer range shooting/hunting. It has the best trigger, an A-2 standard stock, front sight and a Larue rear sight that can replace the scope in seconds to use with irons.

The 2nd has a Vorex SPARC red dot with a quality metal flip up rear sight and standard front sight. Telescoping stock. I haven't tried anything beyond 100 yards with it, but the SPARC dot is 2 MOA and 2"-3" groups are possible at that range. I can co-witness through the dot sight.

The 3rd has a Leupold 1-4X20 scope in QD mounts with a Mag-pul flip up rear mounted under the scope. The scope has to come off to use the rear sight. If I could only keep one, this is the one. The scope on 1X is almost as fast as the dot and at 4X is enough magnification to shoot well out to 200-300 yards. It also makes for a lighter package than with a full size scope and stock. It is easier to see the dot in low light, but it is easier to see the target in low light with a scope.

With either scope I can see the front sight on 2X or less. Between 2X-4X and there may be a small amount of distortion in the bottom part of the scope, but you really have to look for it to notice. Nothing visible above 4X.

I don't see this as a problem once you get used to it. The front sight obstructs just as much of my vision when shooting iron sights only.

trg42wraglefragle
September 17, 2012, 04:15 AM
It'd entirely depend what you want to shoot with your AR.

Are you wanting a hunting/target type set up,
or a plinking led flinging setup?

Or you could buy some flip up sights for it and the quick detach rings and have as many set ups as you want.

Mobuck
September 17, 2012, 07:03 AM
That whole"cowitness with front sight" is basically a nonissue unless you plan to use your rifle as a club/prybar at some point.
As for the distance you can utilize the red dot: your eyesight will determine this since you must be able to discern the target w/o much magnification. I use a 2X Aimpoint out to 200 yards with 60 YO eyes but it's not extremely precise.
My preference is a 1-5x smaller profile scope on a 16" carbine and a higher power magnification variable on the 20" rifles. My logic may be flawed here it is.
The 16" barrel pretty much limits field use on coyotes(my main use for an AR) to 250 yards under most conditions so 4.5-5x is adequate. This type carbine is carried full time from Nov through March so a smaller scope is much easier to handle. The 20" is used more for calling yotes and less packing everywhere I go so the rifle can support a higher power scope w/o getting too unwieldy/heavy. One of my 20" AR rifles has a 4-12x40 ranging/mildot scope which doesn't look out of place nor does it adversly affect the carrying of the already somewhat heavy rifle.

pdogkilr
September 17, 2012, 12:51 PM
Most of your questions have been very well answered. I can't really add much, except I have tried a carry-handle mounted scope.

http://i70.photobucket.com/albums/i106/pdogkilr/Firearms/AR-15/IMG_0964CarbineDiagonalw-LaRue.jpg

I actually liked it, but 65 year old eyes prefer cross-hairs. Having said that, some of the down-sides previously mentioned came into play. And, it was really too high for a collapsible stock.

I changed it to an EOTech, but mounted it in front of the carry handle, since mine is not removable.

http://i70.photobucket.com/albums/i106/pdogkilr/Firearms/AR-15/IMG_1196300DPICarbineRightSideBlack.jpg

This really is a better setup for a general purpose carbine.

I moved the little Leupold to the LWRC in 6.8mm to take advantage of the cartridge's capabilities.

http://i70.photobucket.com/albums/i106/pdogkilr/Firearms/LWRCI%2068-SPC/IMG_1210aLeftClose300-PPISize-1024.jpg

Probably didn't help you much, but I thought some pics might provide insight.

allaroundhunter
September 19, 2012, 12:05 PM
This is a great choice if you add a low-profile rear BUIS like Magpul. Just remember that 3-9x scopes are usually long, but I don't mind it with my AR.

Having a BUIS does you no good if your scope is not in a quick detach mount. The 3-9x is an okay optic for a hunting AR, but not for a carbine length one that is meant for competition shooting or defense.

Unless you are hunting varmints or other small game, the effective range of a 5.56 NATO AR only needs a 4x scope to keep up. 9x is just more magnification than is needed and adds unnecessary weight.

sgms
September 19, 2012, 01:47 PM
There are a number of combination reddot sight out there that will allow you to flip in/out you magnifier allowing you both, they aren't cheap but may do what you are looking for. Check EOTech HHS-II and their MPO-II I think they are that type.

sholling
September 20, 2012, 01:34 AM
Optic selection depends on budget and individual need for example for home defense I have an AR15 with an Eotech (and magnifier) cowitnessed to a fixed front sight and a folding rear sight.

http://i168.photobucket.com/albums/u197/damnfineguy/My%20Toys%20800/3528eeb1.jpg

I have another AR15 that I built for hog hunting and home defense and it has an illuminated 1-4x24 scope in a LaRue quick release mount and backed up by folding sights. Even with the front sight up it doesn't bother me at 1x and I don't even see the front sight at 2x.

http://i168.photobucket.com/albums/u197/damnfineguy/My%20Toys%20800/337ce419.jpg

This 22 might have the solution that you're looking for. It has a Weaver Classic V3 1-3x20 (http://www.natchezss.com/product.cfm?contentID=productDetail&brand=WE&prodID=WE849400&prodTitle=Weaver%20Classic%20V-3%201-3X20%20Riflescope%20Dual-X%20Reticle%20Matte) in a Burris quick disconnect (QD) P.E.P.R. (http://swfa.com/Burris-AR-PEPR-QD-1-Scope-Mount-P48181.aspx) mount with a folding backup sight. It's affordable and don't let the price fool you it's a good scope. With price matching you could be out the door with scope and mount for less than $250. Or for about the same price you could put a Weaver V10 2-10x38 (http://www.natchezss.com/product.cfm?contentID=productDetail&brand=WE&prodID=WE849403&prodTitle=Weaver%202-10X38%20Classic%20V-10%20Riflescope%20Ballistic-X%20Reticle%20Matte) in that P.E.P.R mount. flip-up rear sights run $40-120.

http://i168.photobucket.com/albums/u197/damnfineguy/22s%20-%20800dpi/IMG_0199a.jpg

Justice06RR
September 20, 2012, 04:12 AM
Having a BUIS does you no good if your scope is not in a quick detach mount. The 3-9x is an okay optic for a hunting AR, but not for a carbine length one that is meant for competition shooting or defense.

Unless you are hunting varmints or other small game, the effective range of a 5.56 NATO AR only needs a 4x scope to keep up. 9x is just more magnification than is needed and adds unnecessary weight.

No good? it takes about 5seconds to remove the scope.

This is not for a duty/HD setup; we're talking about hunting or plinking where you have time to switch optics and not in a time rush. a QD mount is nice, but not necessary. For duty use of course you need a better setup, but then we would already know that...

Also 9x is helpful depending on the shooters eyes. i.e. my eyes are not very good at long distances past 150yards (bad eyes and short sightedness doesn't help).

The effective range of an AR in 5.56 is 500meters. I can barely see 150 with iron sights. The 3-9x scope helps a lot if you intend to shoot within these distances, granted its probably better if you have a larger caliber AR (6.8, 6.5, 300, etc).

allaroundhunter
September 20, 2012, 04:55 AM
Again, I said unless you have a quick detach mount, that BUIS does you no good if he has time to switch sights (plunking or hunting), then a folding BUIS is not needed. A fixed rear sight would do much better in that role.

And yes, the effective range of an AR is 500 meters. That typically means minute of person with your 55 gr FMJ rounds. A 4x scope is plenty for that. For varmint hunting, then yes, a higher magnification is a good idea. Again, all points that I previously made.

Sent from my HTC One X

checkmyswag
September 20, 2012, 04:20 PM
Got it down to the following scopes...

Weaver
Nikon

Yes, I am very cost conscious. I've seen these $1500 scopes and see guys recommended them. Suppose people are in a different economic sphere than I or they really really value/need a super high quality scope.

I really like the price on these Weaver models. Getting an illuminated reticle magnified scope for less than $300 is very attractive to me.

Then I'd do with a decent mount and magpul backup rear sight.

Comments/opinions on these models?

http://www.natchezss.com/images/products/WE849400.jpg
http://www.google.com/url?source=imglanding&ct=img&q=http://www.slickguns.com/sites/default/files/WE800702.jpg&sa=X&ei=KYpbUOPRLKrW2AXQs4CQCw&ved=0CAkQ8wc&usg=AFQjCNHNjhJMHo4QpJXnsVj77tZWWhjdIA
http://images1.opticsplanet.com/755-405-ffffff/opplanet-nikon-m223-kit.jpg

http://www.natchezss.com/product.cfm?contentID=productDetail&brand=WE&prodID=WE849400&prodTitle=Weaver%20Classic%20V-3%201-3X20%20Riflescope%20Dual-X%20Reticle%20Matte

http://www.natchezss.com/product.cfm?contentID=productDetail&prodID=WE800701&src=sim

http://www.natchezss.com/product.cfm?contentID=productDetail&prodID=NK8485&src=exrbSrch

madcratebuilder
September 21, 2012, 09:06 AM
I've shot a couple of AR's with the 1-4 Weavers and I own a Nikon 1-4. I think I would go with the Weaver in a Burris PEER mount.

It's a compromise when you try and have a multipurpose AR, most peeps I know end up with three or more variations of the rifle.

http://i32.photobucket.com/albums/d37/madcratebuilder/AR15/sept12ar1.jpg

checkmyswag
September 21, 2012, 10:13 AM
I think I would go with the Weaver in a Burris PEER mount.

I'm getting closer to going this direction. Would like a 1x4 but a 1x3 would be adequate and about $100 or so less from what I see.

Crow Hunter
September 21, 2012, 10:55 AM
I'm getting closer to going this direction. Would like a 1x4 but a 1x3 would be adequate and about $100 or so less from what I see.

One thing to keep in mind is how far you are going to be shooting.

If you are going to keep your shooting within the "flat" part of the trajectory of the round just plain cross hairs are great, nothing to get in the way of your view of the target.

But if you are planning on shooting outside of this range where bullet drop might have a noticable affect on your bullet impact, it is nice to have some reference points built into the reticle so you don't have to try and remember your dope and dial your optic up and down or try to just hold over in space without a point of reference.

With an optic that has a BDC or better yet hash marks/mil-dots, you can just put the portion of the reticle that corresponds to your POI at that range and pull the trigger without having to dial anything.

You can often use the marks for ranging as well.

checkmyswag
September 22, 2012, 05:14 PM
I'm trained to shoot up to 300m so probably will just stick with that. I'm very comfortable and experienced out to that range.

I appreciate the mil dots and BDC reticles but don't need/want one.

Justice06RR
September 24, 2012, 08:57 PM
Again, I said unless you have a quick detach mount, that BUIS does you no good if he has time to switch sights (plunking or hunting), then a folding BUIS is not needed. A fixed rear sight would do much better in that role.

And yes, the effective range of an AR is 500 meters. That typically means minute of person with your 55 gr FMJ rounds. A 4x scope is plenty for that. For varmint hunting, then yes, a higher magnification is a good idea. Again, all points that I previously made.


I get your point, but the point i'm making is that BUIS are not useless.

If you are out in the woods or on duty and your optic becomes unusable i.e. you drop the rifle and the glass breaks, or some type of malfunction etc, you will need to switch to your BUIS-- hence why they are called Back Up Iron Sights.

The problem with a fixed rear sight is that sometimes it does not fit under an optic. Also you cannot cowitness with a magnified optic, but i'm sure you already knew all that..

Are you saying that AR's with optics don't need BUIS?

allaroundhunter
September 24, 2012, 10:09 PM
Are you saying that AR's with optics don't need BUIS?

No, this is what I have said multiple times in this thread:

Again, I said unless you have a quick detach mount, that BUIS does you no good; if he has time to switch sights (plinking or hunting), then a folding BUIS is not needed. A fixed rear sight would do much better in that role.


An AR made to be a varmint rifle does not need to have a quick detach mount because the rifle will not be run in a situation in which BUIS will even come into use if the optic fails for some reason. If you are hunting and you drop your rifle hard enough to destroy an optic, pack up and leave because it just is not your day. BUIS will not help you in that situation.

If you put a magnified optic on a duty rifle and don't use a quick detach mount, then you are waiting for Murphy's law to hit you in the face. A duty rifle should either have a magnified optic with a quick detach mount with BUIS, have a red dot/holographic sight with BUIS that will co-witness (quick detach mount or no, doesn't really matter), or have fixed iron sights.

compdocjoe
September 25, 2012, 08:29 AM
This setup worked really good for me.
http://i371.photobucket.com/albums/oo151/insider/Bushmaster.jpg