Scope recommendations for KD AR

[Lomshek]

I hope you guys know that you are really bad for me. Now I'm going to have to build ten new rifles, one for each optic recommended here...

But honey the guys on the forum said I had to do it!

[ITB]

I have two 20" ARs that I use for distance shooting.  While I initially earned my patch 10 years ago with an iron-sighted AR, my aging eyes and worsening astigmatism necessitate optics.   

The first has a Trijicon ACOG.  The TA31F 4x32 with the BDC Chevron reticle.  Works very well, and it has a growing track record for making full-distance Riflemen.  Two separate people have taken it out on the KD range and earned their full distance patch on their first AQT.  Both had never fired the rifle before.

This is the reticle:


When properly zeroed, the tip of the chevron is your 100 yd aiming point, the underside of the chevron is 200 yards, the top of the vertical illuminated line is 300, and the 4 and 6 hash marks are 400 and 600 yards respectively.  The horizontal lines are also the width of a man at those distance (19"), so it's easy to range your target.

FYI, as an aside - be aware that certain optics should not be "boxed."  Trijicon is one of my largest customers in my day job.  I know most of the engineers, and I'm there on an almost weekly basis.  They were emphatic that the ACOGs should not be boxed.  The adjusters are designed to be set for BSZ for the rifle, and then left alone.  Even when you are making that initial zero setting, they recommend a few clicks, then tap the body of the scope a few times, a few more clicks, a few more taps, and so on.

The second rifle has a Vortex Viper HS 2.5-10 FFP scope.  This is from the Kimball/Blue Water KD event:

I hate it when others shoot my rifle better than I can....
Grindstone was holding right at -10 MOA on the reticle, right edge of the target to compensate for wind.

This is the reticle - a little "busier" than the ACOG, but useful once you get used to it and dial it in for your particular rifle:


Both optics have their strengths and weaknesses.  For slower fire, precision work, I'd probably go with the scope.  But if I ever get a chance to go on MTC's UKD popup range, where I'd have to range and take the shot quickly, the ACOG would be the better choice.  Less magnification, but less thought needed as well.

[SteelThunder]

Paraphrasing what Bill Winkle told me at Atterbury

"SteelThunder Grindstone can be on my fire team"

[Nashville Stage]

FYI, as an aside - be aware that certain optics should not be "boxed."  Trijicon is one of my largest customers in my day job.  I know most of the engineers, and I'm there on an almost weekly basis.  They were emphatic that the ACOGs should not be boxed.  The adjusters are designed to be set for BSZ for the rifle, and then left alone.  Even when you are making that initial zero setting, they recommend a few clicks, then tap the body of the scope a few times, a few more clicks, a few more taps, and so on.

That's interesting; I haven't heard this before. As an engineer, that got me curious. Next time you're up that way, would you mind asking their guys to elaborate on it? The Trijicon people are smart cookies, and I'm sure there's a good reason. I wonder if the same logic might apply to other optics that I (or our students) have.

[Lomshek]

FYI, as an aside - be aware that certain optics should not be "boxed."  Trijicon is one of my largest customers in my day job.  I know most of the engineers, and I'm there on an almost weekly basis.  They were emphatic that the ACOGs should not be boxed.  The adjusters are designed to be set for BSZ for the rifle, and then left alone.  Even when you are making that initial zero setting, they recommend a few clicks, then tap the body of the scope a few times, a few more clicks, a few more taps, and so on.

That's interesting; I haven't heard this before. As an engineer, that got me curious. Next time you're up that way, would you mind asking their guys to elaborate on it? The Trijicon people are smart cookies, and I'm sure there's a good reason. I wonder if the same logic might apply to other optics that I (or our students) have.

It makes sense as the ACOG (and most other scopes) are designed to be zeroed and left alone.  Dialing dope is not something 99% of scope users ever do and so scope click repeatability or consistency is not a concern beyond academic interest.  Instead it becomes a case of adjust the scope, fire a few rounds (or whack it) and repeat as needed until the scope settles into a zero.

If the scope has a little lateral drift as you dial 5 vertical MOA to get zeroed or the click value is .59MOA instead of .5MOA that doesn't really change the ability to zero the scope it just may take a few extra rounds as you get through the fine tuning of it rather than it working out mathematically perfectly.

[SteelThunder]

I'm just completely speculating here but it at least it is based on past (well...very long ago) experience as a recovering engineer (step 11 of the 12)

As Lomshek notes above, I can see that behavior if an optic is truly designed to be "set and forget".  You only design a product to meet the specific use case for which it is intended...otherwise you're putting money and time into something that isn't worthwhile.  ACOG (maybe but for cripes-sake, for the stupid price, you'd think they'd make erectors that more durable) must be one of those.  I'd posit that a LOT of your less-expensive, hunting style scopes are designed that way also.

But for ANY scope that is set-up for long range tactical, PRS or XTC (across the course) shooting, if that's the procedure?  Throw it in the trash.  These sports DEMAND constant range estimation and dope on the scope.

FYI, as an aside - be aware that certain optics should not be "boxed."  Trijicon is one of my largest customers in my day job.  I know most of the engineers, and I'm there on an almost weekly basis.  They were emphatic that the ACOGs should not be boxed.  The adjusters are designed to be set for BSZ for the rifle, and then left alone.  Even when you are making that initial zero setting, they recommend a few clicks, then tap the body of the scope a few times, a few more clicks, a few more taps, and so on.

That's interesting; I haven't heard this before. As an engineer, that got me curious. Next time you're up that way, would you mind asking their guys to elaborate on it? The Trijicon people are smart cookies, and I'm sure there's a good reason. I wonder if the same logic might apply to other optics that I (or our students) have.

It makes sense as the ACOG (and most other scopes) are designed to be zeroed and left alone.  Dialing dope is not something 99% of scope users ever do and so scope click repeatability or consistency is not a concern beyond academic interest.  Instead it becomes a case of adjust the scope, fire a few rounds (or whack it) and repeat as needed until the scope settles into a zero.

If the scope has a little lateral drift as you dial 5 vertical MOA to get zeroed or the click value is .59MOA instead of .5MOA that doesn't really change the ability to zero the scope it just may take a few extra rounds as you get through the fine tuning of it rather than it working out mathematically perfectly.

[Quinncannon]

For my AR15's, I have found that the Vortex Viper PST 1x4 scopes and the SWFA Super Sniper in 6 or 10 power are excellent for KD and even the reduced course.

I have used the Super Snipers for many years, I have found that they are bull strong and the target turrets are easy to use, the adjustments are spot on, up and down.

I've been using the Vortex for the last couple of years, seems very well made with the same ease of use with the turrets and the come ups and downs are spot on as well.

I have a Super Sniper on my LRB M14SA as well, works perfectly for my use.

[airplanejoe]

I'll try to simplify where this thread is heading. My 0.02 cents: the best scope is the one you now have and are familiar with.
aj

[AJ Gonzales]

The "set it and forget it" thing is for prism scopes. You'll notice the capped turrets on ACOG and Primary Arms ACSS prism scopes. The "tap it to get the scope to settle" thing is a byproduct of the prism and supporting mechanism.

Dialing in firing solutions is great for precision work, but for AS, it's not precision shooting.

[desert_diver]

The scope recommendations are helpful, but I'd like to get input from the community on my use case.  I built a 6.5 Grendel upper for my AR-15 lower.  I would like a scope suitable for use at 1k yds+.  My intent is to have equipment which won't handicap me at TaosGlock & BlueFeather's UD event (for example, https://appleseedinfo.org/smf/index.php?topic=54380.0). 

Is 8x magnification enough for 1k yds? 
What is the preference for 1st Focal Plane vs 2nd Focal Plane?  I'm leaning towards FFP, simply because I think it simplifies ranging of targets. 
$500 is about my limit. 

Any inputs would be welcome. 

[Nashville Stage]

Personally, I'd go for a second focal plane scope for two reasons:
- You'll usually wind up doing target identification & range estimation at max magnification anyway.
- You'll get a better quality scope for the money with a second focal plane, since FFP comes with a significant price jump. You're going to have a hard time finding a decent quality FFP scope under $500.

[AJ Gonzales]

The scope recommendations are helpful, but I'd like to get input from the community on my use case.  I built a 6.5 Grendel upper for my AR-15 lower.  I would like a scope suitable for use at 1k yds+.  My intent is to have equipment which won't handicap me at TaosGlock & BlueFeather's UD event (for example, https://appleseedinfo.org/smf/index.php?topic=54380.0). 

Is 8x magnification enough for 1k yds? 
What is the preference for 1st Focal Plane vs 2nd Focal Plane?  I'm leaning towards FFP, simply because I think it simplifies ranging of targets. 
$500 is about my limit. 

Any inputs would be welcome.

I think you'll have a tough time with 8x at those distances. Look at what the PRS guys are using. High mag, mil grid reticles, FFP, but $$$$$$.

For what it's worth, the primary arms 4-14x FFP scopes are pretty decent. Are they nightforce clear? No. Are the clicks Kahles crisp? Nah. Is it good enough if you're ballin' on a budget? Probably. FFP removes one more variable when you're ranging or using the holdovers, and I think that's very valuable. If you goof and don't have it dialed all the way up, you're not going to be making big errors like you might be with a SFP scope.

This is supposed to be a step up from the 4-14 and might fit your needs well:
https://www.primaryarms.com/pa-3-18x50mm-illuminated-ffp-rifle-scope-with-acss-apollo-6-5cm-reticle

I've been nothing but impressed with my PA stuff so far. Zero complaints, and my bank account is thankful!

[NJrefugee]

I have a 6.5 Grendel upper for my AR as well. I bought a used Vortex Viper PST Gen1 4-16 FFP for $600, including the scope rings/base. Shooting with a bipod, it is easily hitting 2MOA targets at 800 and 1000. At those distances, I have it up to 16x. I suppose 8x would work for 4MOA targets, since the targets would be twice the size. 

My two cents would be to go with the scope with the highest low-end magnification that would work for your purposes (outside of KD), in order to give yourself the highest magnification options in case you feel like cranking it up.
For me, I can't think of too many situations in which I'd be using this rifle and need to be below 4x, so I got 4-16. Definitely get FFP.

Look at the Equipment Exchange on AR15.com, used optics for sale.  Vortex has a great warranty so no issues buying one used. Since the Gen2 versions came out, lots of guys have been selling the Gen1 to trade up. Be patient, as items cycle through continuously.  Plenty of good stuff from other manufacturers on there as well.

[LogCabinShooter]

 If you're ok with a fixed magnification, look at SWFA. $300 will get you a first class optic in first focal plane that tracks extremely well. As for Primary Arms, I have a 4-14x in FFP, and IMO everything about it is lacking. Also, its about an inch longer at the back of the scope than any other scope I own, forcing you to have an unnatural cheek weld. Also only has a 3 year warranty. It was money wasted. 
As far as required magnification for 1k yards, it depends on target size and purpose. If you're into precision shooting, forget the AR platform, the 6.5 Grendel, and the $500 scope idea. If you just want ring some steel on a 4 MOA target, put a 10 or 12x SWFA on it and have some fun. Any more than that and you'll be fighting mirage more often than not.

[AJ Gonzales]

If you're ok with a fixed magnification, look at SWFA. $300 will get you a first class optic in first focal plane that tracks extremely well. As for Primary Arms, I have a 4-14x in FFP, and IMO everything about it is lacking. Also, its about an inch longer at the back of the scope than any other scope I own, forcing you to have an unnatural cheek weld. Also only has a 3 year warranty. It was money wasted. 
As far as required magnification for 1k yards, it depends on target size and purpose. If you're into precision shooting, forget the AR platform, the 6.5 Grendel, and the $500 scope idea. If you just want ring some steel on a 4 MOA target, put a 10 or 12x SWFA on it and have some fun. Any more than that and you'll be fighting mirage more often than not.

The 4-14x is a very long scope. It absolutely demands a long cantilever mount.

[desert_diver]

Thanks to all those who shared their experience!