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I have an aimpoint pro that I just put back on my ar. And have it sighted in for 25yds. But I want to throw a set of backup irons on too for longer shots and zero it out at 100yds. I still want to be able to pot shot prairie dogs with it and don’t want to just use the red dot, dammed astigmatism. I’m wanting flip up sights. Any specific ones I should look at?
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Countless good options depending on your budget.
Anywhere from Magpul, Troy to KAC. I have ones from those three and all seem to work just as advertised.
I have slight astigmatism as well, but I would rather use an RDS at distance than irons. Just me though.
Aimpoint zeroed for 100yds; if your goal is 100yd. zero.
Not really an issue to use at closer distances.
I would use the Aimpoint for longer ranges and the irons for backup with your preferred zero.
Have taken Aimpoints out to 400yds. during classes.
Prefer Troy BUIS.
i have midwest industries CRS-R with my comp m4s - solid rear sight in my opinion
bamashooter
12-31-19, 13:03
The basic polymer MBUS are just fine imo. Regarding the eyeball, I would recommend a future purchase of a prism scope between 2- 3x. Very nice for your 100m shots yet very easy (perhaps 10 minutes max) to get adapted to that magnification firing a 5-7 meters or so. To keep me in the comfort zone for close-in stuff using my prisms, I grab one 2-3 times a week and just simulate looking at nearby objects. Though it's not really needed, it's so simple to do and my close-in adaption is perfect. I don't have any eye issues but I really like my prisms, especially my 2 magnified one.
I have the Vortex 1x which is ok; no problems. I also have the Primary Arms 2.5x on a 5.56 pistol and their 3x on a .300blk pistol. Everything is zeroed at 50m. Don't really need the magnification (20/10 in both eyes) but I appreciate it.
lordmorgul
12-31-19, 13:15
Personal opinion is you should zero at 100 for both systems and learn the appropriate offset for closer, you do need it but it’s not that complicated to try and consistently learn it.
If you keep what you’ve got, you need to decide if you want a quick adjustable (elevation/range) rear iron or not.
For basic flip up Aero Precision also makes a nice set, with HK style front sight wings if you like that (I do). I have two sets of those, only one installed on a rifle which has an RDS in it also.
I also use offset 45 degree sights, and I think it’s the best option for having an option of longer range adjustable sights with you. It’s got the standard A2 elevation wheel, and works quite well. Since I do not have a standard RDS with these sights but LVPO and Prism sights, you cannot cowitness so the offset is a viable way to go.
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Andrew - Lancaster, CA
NRA Life Member, CRPA member, Calguns.net contributor, CGF / SAF / FPC / CCRKBA / GOA / NAGR / NRA-ILA contributor, USCCA member - Support your defenders!
Why would you want an Aimpoint zeroed at 25 and irons at 100? Just do both at 50m.
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I have an aimpoint pro that I just put back on my ar. And have it sighted in for 25yds. But I want to throw a set of backup irons on too for longer shots and zero it out at 100yds. I still want to be able to pot shot prairie dogs with it and don’t want to just use the red dot, dammed astigmatism. I’m wanting flip up sights. Any specific ones I should look at?
I would try to trade your Aimpoint PRO for an etched reticle optic such as a Vortex Spitfire (simple concentric circle reticle). I have switched to these sights (etched reticle) on anything using a RDS except my SBR which wears an Aimpoint PRO because I leave it on.
The Burris AR 332 is also an etched reticle sight and has a very usable reticle, it's only drawback for me was it's a fixed 3 power, so not ideal for inside 25 yards, I would not recommend the Burris AR-1X, as the reticle is too small and 'busy.'
These are all good, budget optics.
I would also zero at either 50 or 100 yards, with a 25 yard zero you are way high for the useful range of the rifle for most people (100 to 200 yards).
These sticky threads from the top of the AR General Discussion forum might be helpful:
https://www.m4carbine.net/showthread.php?107572-Zen-of-the-100-Meter-Zero
https://www.m4carbine.net/showthread.php?65679-AR-15-Zeros-and-Trajectories
Before you make a final decision regarding the Aimpoint dot and your astigmatism, make sure you view the dot while looking through a small aperture rear sight. I and others have found that the squiggeldy-gook of the astigmatism dot is noticeably improved while looking at it through the rear sight. There are physical reasons for this I learned in a freshman physics class I surely cannot articulate in a forum post but, rest assured, there's real science behind the why and not just people being convinced to see something. So...be sure to try it if you haven't (and it's basically that the light towards the edge of your eye/lense is more distorted than the middle it's why people with poor eyesight and glasses off can look through a pinhole in paper and see better)
Simple explanation: the light rays coming through the smaller aperture are more sharply focused and hit a smaller portion of the retina which sharpens the vision. This is the same principle that results in increased depth-of-field (increased focus throughout the image) when using a higher f-stop during photography.
Why would you want an Aimpoint zeroed at 25 and irons at 100? Just do both at 50m.
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That’s what I do, works out well and is right on out to 500 yards.
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That is a main reason I have BUIS with a RD- to clean up distorted Dot with rear (like a "Merit" diopter that Bullseye shooters use(ed) for a precision shot.
I shoot "Absolute Co-witness" mounts- the rear BUIS in conjunction with RD works well to maybe three hundred yds. for me.
I don't know if using a "Lower Third" mount would create issues with Parallax at distance, but seems it might- your pupil wouldn't be directly behind the Dot.
Any direct experience using Lower Third mount and REAR BUIS at distance would be welcome.
Renegade04
01-01-20, 10:20
Depending on how much you want to spend, I would recommend looking at the following:
MAGPUL MBUS sights
MAGPUL MBUS PRO sights
Midwest Industries Combat Rifle Sights
LMT Imperial 5.56 sights
Troy Industries BUISs
grizzlyblake
01-01-20, 14:41
That is a main reason I have BUIS with a RD- to clean up distorted Dot with rear (like a "Merit" diopter that Bullseye shooters use(ed) for a precision shot.
I shoot "Absolute Co-witness" mounts- the rear BUIS in conjunction with RD works well to maybe three hundred yds. for me.
I don't know if using a "Lower Third" mount would create issues with Parallax at distance, but seems it might- your pupil wouldn't be directly behind the Dot.
Any direct experience using Lower Third mount and REAR BUIS at distance would be welcome.
Somebody on here a while back talked about how their MRO was 6" off at 100yd when using a lower 1/3 buis like you describe.
When using the RDS while sighting through a rear peep sight... is there an advantage to even having the RDS?
The red dot presents a single aiming point. A rear sight plus front sight are two aiming points. A rear sight plus a red dot also seems like two aiming points. Just curious if there is still a benefit, maybe low light or something?
Somebody on here a while back talked about how their MRO was 6" off at 100yd when using a lower 1/3 buis like you describe.
This is what I would suppose, which would be entirely unacceptable for me.
And good question jediguy.
My answer is yes, there is an advantage.
In terms of sighting systems there is nothing quicker, reasonably precise and as light as a RD.
I expect to use my carbine at relatively close range; 75 yds and in, which works for me because the astigmatism altered dot is GTG with a degree of accuracy to that range.
If using rear BUIS increases my consistent ability to make hits to over 200 yds by sharpening my sight picture-
It is worth it.
So, generally use only RDS for general expected engagement distances, then utilize the irons with red dot for reaching further out. Do I have your intent correct? Or do you “always” use rear with RDS?
Either way, very interesting, and not something I had considered.
When using the RDS while sighting through a rear peep sight... is there an advantage to even having the RDS?
The red dot presents a single aiming point. A rear sight plus front sight are two aiming points. A rear sight plus a red dot also seems like two aiming points. Just curious if there is still a benefit, maybe low light or something?
You don't need to align the dot in the middle of the rear as you would a front sight post. You do need a little better/more consistent cheek weld/eye positioning that you would for an RDS without the rear sight in order to, well, be looking through that rear sight. You can sight through an RDS and co-witnessed irons and see this. Also low light. Also you can move the rear sight up or down depending on conditions. Like, if it's sitting for home defense, fold the rear down. If you're going out or shooting at longer distances etc, flip it up
So, generally use only RDS for general expected engagement distances, then utilize the irons with red dot for reaching further out. Do I have your intent correct? Or do you “always” use rear with RDS?
Either way, very interesting, and not something I had considered.
Yes, I flip rear up if circumstance and time permit a precise shot; partial head at 60 yds, “bad guy” at 200+ yds as example.
The smaller aperture, while crisping up dot and sight picture (think smaller camera aperture increasing depth of field), DOES darken the image for me- to the point that in low light it is nearly useless.
This is where the weight and arguably the trade off of speed of engagement of a LPV are the answer- for me.
Mr McSimon
01-01-20, 16:38
You don't need to align the dot in the middle of the rear as you would a front sight post. You do need a little better/more consistent cheek weld/eye positioning that you would for an RDS without the rear sight in order to, well, be looking through that rear sight. You can sight through an RDS and co-witnessed irons and see this. Also low light. Also you can move the rear sight up or down depending on conditions. Like, if it's sitting for home defense, fold the rear down. If you're going out or shooting at longer distances etc, flip it up
Also, you can still pick up the dot if it's outside the aperture of the rear site, it just focuses in nice and sharp once you acquire the straight line of vision. Troy's present well for this, but the default aperture for them is the large size. With the Diamond Head Goalpost style BUIS (https://bravocompanyusa.com/bcm-folding-sight-rear-mfg-by-diamond-head-black/), you can choose which size you prefer as default. Those are my favorites to run with red dots for precisely the reason being discussed. My second favorite choice would probably be Magpul Pro's, but they tend to cover more of the field of view.
Why would you want an Aimpoint zeroed at 25 and irons at 100? Just do both at 50m.
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Because I don’t want them at 50. If I wanted them at 50 that’s what I would do. I want the red dot for more home defense, close up. Irons anything else other than that. Two different situations, one gun.
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Depending on how much you want to spend, I would recommend looking at the following:
MAGPUL MBUS sights
MAGPUL MBUS PRO sights
Midwest Industries Combat Rifle Sights
LMT Imperial 5.56 sights
Troy Industries BUISs
I can’t seem to find the lmt they’re out of stock. That was my first thought. I have a magpul rear and just don’t like it.
On the Troy, any suggestions regarding DOA rear sight?
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Mr McSimon
01-01-20, 20:03
Because I don’t want them at 50. If I wanted them at 50 that’s what I would do. I want the red dot for more home defense, close up. Irons anything else other than that. Two different situations, one gun.
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You're remark is a little flippant. I know you didn't ask advice about you're zero, but people are trying to help you anyways. The zero preference you've stated doesn't make a lot of sense. There are certainly better options for what you say you're trying to accomplish, but it's clear you haven't done the proper research or had the proper training to see that.
I started with Magpul Mbus, went to the Magpul Pro's and ended up settling for KAC Micro's with my Aimpoint. Might have to find what your personal preferences wind up being
I started with Magpul Mbus, went to the Magpul Pro's and ended up settling for KAC Micro's with my Aimpoint. Might have to find what your personal preferences wind up being
Ok. I’m thinking kac, Troy or lmt.
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shadowrider
01-01-20, 23:16
I've got a set of GG&G because that's all I could find at the time. They seem GTG but I don't use them much because...Aimpoint.
I zero my Aimpoint PRO at 25 and can still make hits at 300 on a 10" steel plate. Don't know the actual hold the dot covers it all up, but the hits come if I center the dot over it. M193 is the ammo.
Ok. I’m thinking kac, Troy or lmt.
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I have Troys on 2 rifles, really like them. I didn’t care for the magpuls
just personal taste. I like the look of the bobros, very compact I may try them in the future.
I've got a set of GG&G because that's all I could find at the time. They seem GTG but I don't use them much because...Aimpoint.
I zero my Aimpoint PRO at 25 and can still make hits at 300 on a 10" steel plate. Don't know the actual hold the dot covers it all up, but the hits come if I center the dot over it. M193 is the ammo.
You aren't getting first round hits are you? How many hits out of ten? At 300 yards you dot should be covering 6 inches of the plate, if you are centered on the plate, your rounds should be about 3 inches above the plate. With a 50 yard zero at 300 yards, your rounds should just barely go under the plate, assuming center hold.
Hornady BC - m193: BC= .243; VEL= 3150; SIGHT HEIGHT= 2.6
First number in ( ) is trajectory for 25 yard zero; second number in ( ) is for a 50 yard zero.
0 - (-2.6) (-2.6)
25 - ON (-1.2)
50 - (+2.3) ON
75 - (+4.4) (+0.9)
100 - (+6.3) (+1.6)
125 - (+7.7) (+1.9)
150 - (+9) (+2) 50 yard zero highest point above sight line
175 - (+9.8) (+1.7)
200 - (+10.4) (+1.1)
225 - (+10.5) (+0.1) 25 yard zero highest point above sight line
250 - (+10.3) (-1.3)
275 - (+9.6) (-3.1)
300 - (+8.4) (-5.5)
325 - (+6.8) (-8.3)
350 - (+4.5) (-11.7)
375 - (+1.7) (-15.7)
400 - (-1.8) (-20.3)
425 - (-6) (-25.7)
450 - (-10.9) (-31.8)
475 - (-16.7) (-38.7)
500 - (-23.4) (-46.6)
If you look at the numbers, it just seems to me that the 50 yard zero is more useful with a RDS inside 350 yards.
That is a main reason I have BUIS with a RD- to clean up distorted Dot with rear (like a "Merit" diopter that Bullseye shooters use(ed) for a precision shot.
I shoot "Absolute Co-witness" mounts- the rear BUIS in conjunction with RD works well to maybe three hundred yds. for me.
I don't know if using a "Lower Third" mount would create issues with Parallax at distance, but seems it might- your pupil wouldn't be directly behind the Dot.
Any direct experience using Lower Third mount and REAR BUIS at distance would be welcome.
I found that a buis does indeed clean up red dot astigmatism. I have dd1.5 on two rifles with red dots that are lower 1/3. These red dots agree with my eyes and they also track well within the parallax constraints of the optics. However, on a third carbine, the mro was a different beast with bad astigmatism AND parallax. I had to go with a absolute cowitness to make it work. The iron sight and red dot together does make a busy sight picture especially as the front sight does obscure the target area. If I had to do it over again? Probably get a lpvo...
lordmorgul
01-02-20, 15:04
A 1x prism with etched reticle like Vortex Spitfire is great option for this due to much better parallax behavior than LPVO at 1x and less busy than RDS co-witness and no astigmatism issue are all which is even better, but I still have the offset 45deg iron because I see it worth the weight penalty and that way it matches my SPR rifle with LPVO for how I’d use a backup sight.
I was doubtful I’d like the Spitfire at first due to the smaller field view than the full size Strikefire RDS, but after trying it awhile I do prefer it and switched.
Andrew - Lancaster, CA
NRA Life Member, CRPA member, Calguns.net contributor, CGF / SAF / FPC / CCRKBA / GOA / NAGR / NRA-ILA contributor, USCCA member - Support your defenders!
lordmorgul
01-02-20, 15:10
That is a main reason I have BUIS with a RD- to clean up distorted Dot with rear (like a "Merit" diopter that Bullseye shooters use(ed) for a precision shot.
Do you have a BUIS set that has both size rear apertures? I’m curious if the larger aperture cleans up the RDS as much as the smaller one; I would guess smaller is better but marginally or a lot? My BUIS has both but I haven’t been paying attention to check this and the thread brought the question to mind.
My Aero Precision rear BUIS has two sizes flip up like A2 sights.
Andrew - Lancaster, CA
NRA Life Member, CRPA member, Calguns.net contributor, CGF / SAF / FPC / CCRKBA / GOA / NAGR / NRA-ILA contributor, USCCA member - Support your defenders!
A 1x prism with etched reticle like Vortex Spitfire is great option for this
I’d be interested in reading a full review thread on this optic, if you can.
shadowrider
01-03-20, 08:04
If you look at the numbers, it just seems to me that the 50 yard zero is more useful with a RDS inside 350 yards.
Agreed and that's why I use it. I can just ditch worrying about holdover out to 300 and not worry about much else. It works for me and I like simple.
Do you have a BUIS set that has both size rear apertures? I’m curious if the larger aperture cleans up the RDS as much as the smaller one; I would guess smaller is better but marginally or a lot? My BUIS has both but I haven’t been paying attention to check this and the thread brought the question to mind.
My Aero Precision rear BUIS has two sizes flip up like A2 sights.
Andrew - Lancaster, CA
NRA Life Member, CRPA member, Calguns.net contributor, CGF / SAF / FPC / CCRKBA / GOA / NAGR / NRA-ILA contributor, USCCA member - Support your defenders!
The large aperture does not "sharpen up" the Dot/sght picture nearly as well as the smaller one for me.
This with Magpul Pros and Troy BUIS.
Strength Of Arms
01-03-20, 14:45
I bought an offset Magpul pro set for myself for Christmas. Installing them last night and I over-torqued and snapped the hex screw head right off. I called them this morning to maybe order a new base or find a way to get the screw out and they said don't worry about it. Here's an RMA and we'll send you a replacement for free. I broke their part and they replaced it for free. The customer service is blowing me away. They've certainly earned my ongoing business.
Do you have a BUIS set that has both size rear apertures? I’m curious if the larger aperture cleans up the RDS as much as the smaller one;
For me it does not. Has to be the small aperture. That's why I generally leave it down with the option of flipping up if the situations calls for it
*I'm just some guy there's no reason to listen to me on training stuff etc, but I'm a shooter with astigmatism and I own all the things being discussed so I can at least speak to how things look. For specific sights + red dot I have tried Aimpoint and Sparc AR combined with MBUS2, MBUS Pro, and Troy
lordmorgul
01-03-20, 16:06
I bought an offset Magpul pro set for myself for Christmas. Installing them last night and I over-torqued and snapped the hex screw head right off. I called them this morning to maybe order a new base or find a way to get the screw out and they said don't worry about it. Here's an RMA and we'll send you a replacement for free. I broke their part and they replaced it for free. The customer service is blowing me away. They've certainly earned my ongoing business.
Awesome. I have to admit I did the same thing to one of the Aero Precision sets, snapped right off where the rail mating angle ends (a natural stress concentration point). AP Replaced the sight for free.
Andrew - Lancaster, CA
NRA Life Member, CRPA member, Calguns.net contributor, CGF / SAF / FPC / CCRKBA / GOA / NAGR / NRA-ILA contributor, USCCA member - Support your defenders!
If you want to shoot range with iron, get something that is ranging like KAC, LMT, MaTech, and a few others are making BDC irons.
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