Best barrel length for NF 1-8 ATACR?

[BallisticHarmony]

I’m looking for the shortest barrel length possible while still being capable at ranges that require the 8x end. Essentially I want to fully utilize the magnification range of the optic while keeping the rifle as compact as I can.

How far can one reasonably hit a 12” target with a 77-gr bullet and 8x magnification?

I’m stuck between 14.5, 16 and 18. Also thinking about pairing the ATACR with the Scalaraworks LEAP/Scope and Magpul bipod. Any thoughts on that are appreciated as well.

[markm]

You can do 14.5 with 77s. With a good spot, we aim to punch the 7" flapper at 750 yards using good 77 gr handloads. For 1000 yards, you're working to hit that 12", especially if there's wind/variable winds.

[crosseyedshooter]

You can check with a ballistic calculator but you'll need the muzzle velocity with your different barrels. For my case, I think Magtech 77gr is transonic around 750 yards out of a 20" barrel. I could probably make it to 650 yards with a 14.5". It'll be roughly 6 mils drop while the ATACR reticle has up to 10 mils, almost as if they had a bigger cartridge in mind.

This is just purely academic looking at ballistic range and not considering wind drift or effective bullet energy.

Here's what a 12" target might look like at 700 yards with the ATACR reticle:

https://i.imgur.com/WkJCBb2l.png

[BallisticHarmony]

That’s very helpful, thanks. Seems like based off that, maybe the ATACR is overkill for the supersonic range of 5.56...? Maybe the NX8 would be a lighter, more realistic option...?

[BallisticHarmony]

Upon further examination, the NX8 has 10 Mils of drop as well.... Seems like overkill, but I still want the best LPVO for my carbine. Since the ATACR has better glass I’ll probably still go with that.

[crosseyedshooter]

I think choosing a barrel to maximize the use of drops on the optic reticle is probably backwards anyway. It makes more sense to choose barrel and optic based on intended use cases. Target shooting to maximum distance vs effective man-stopping or hunting or indoor home-defense all have different and sometimes competing criteria.

[markm]

For what it's worth, trans-sonic has not been an issue AT ALL for us with 77 gr SMKs. The ONLY time that has shown to be problematic is out of my 20" 1/12 .308 combined with 168 gr SMKs. I really saw fanning.

77s in a 1/8 or 1/7??? No sweat beyond super sonic ranges... at least at our altitude.

[BallisticHarmony]

For what it's worth, trans-sonic has not been an issue AT ALL for us with 77 gr SMKs. The ONLY time that has shown to be problematic is out of my 20" 1/12 .308 combined with 168 gr SMKs. I really saw fanning.

77s in a 1/8 or 1/7??? No sweat beyond super sonic ranges... at least at our altitude.

So you don’t think it’s necessary to go any longer than 14.5” for most 5.56 engagement distances if using SMK/TMK? What about 70 TSX?

[Stickman]

So you don’t think it’s necessary to go any longer than 14.5” for most 5.56 engagement distances if using SMK/TMK? What about 70 TSX?


Engaging what, or whom? What distances are you looking at using the weapon? Markm shooting on his 1k KD backyard range is awesome, but if you can’t shoot farther than 200 yards around your locale than it is a moot point.

Hopefully that makes sense. You may find yourself with the wrong optic if distance is your primary focus, especially if it end up being unrealistic.

[markm]

Engaging what, or whom? What distances are you looking at using the weapon? Markm shooting on his 1k KD backyard range is awesome, but if you can’t shoot farther than 200 yards around your locale than it is a moot point.

Exactly. The original parameter was to ding a 12" plate. That said... at our elevation, 14.5 with cut it with ease. As far as TSX, I will never shoot that nonsense, so I'll leave that to the Texas Hog hunters to address.

[WS6]

Exactly. The original parameter was to ding a 12" plate. That said... at our elevation, 14.5 with cut it with ease. As far as TSX, I will never shoot that nonsense, so I'll leave that to the Texas Hog hunters to address.

What do you have against tsx? I've found it accurate and effective, fwiw

[jsbhike]

Finger stutter

[jsbhike]

You can make use of 8x at relatively short distances with the right combinations of target size/color/shape, what is in the area around the target, and lighting conditions.

[grizzman]

On the presumption that you don't own the optic....

Have you considered the NX8? It may not be at the same level as the ATACR, but it also isn't priced like one (and weighs less also).

[boardsnbikes]

Be aware the FC-DM and FC-MIL reticles have a 1.25 moa (0.35 mil) "red dot" center. For precision work, that's pretty thick for a point of aim although entirely acceptable for other purposes.

[crosseyedshooter]

Be aware the FC-DM and FC-MIL reticles have a 1.25 moa (0.35 mil) "red dot" center. For precision work, that's pretty thick for a point of aim although entirely acceptable for other purposes.

I dial down one or two mils to use the sub tensions for groups at 100. Here's a 2" target at 100 yards with -1 and -2 mils dialed.

As long as the target has a light colored background, I don't think group size will be limited by the scope.

https://i.imgur.com/g6tu2BVh.png

https://i.imgur.com/naOkyIAh.png

[Pappabear]

I dial down one or two mils to use the sub tensions for groups at 100. Here's a 2" target at 100 yards with -1 and -2 mils dialed.

As long as the target has a light colored background, I don't think group size will be limited by the scope.

https://i.imgur.com/g6tu2BVh.png

https://i.imgur.com/naOkyIAh.png

Crosseye, thats cool stuff. Me and a friend bought the damn ( I damn the guy that posted the LMT uppers for $699 on Brownells) uppers on Brownells. He wanted a NF 1-4 for that 10.5 upper. I Said why not get the 1-8, just why not? Having more long end mag is never a bad thing as long as you have enough short range stuff. I would like the NX8 on mine if I had the $$$$ with off set KAC irons. Lotta scope for a 10.5 but it never hurts. A precision shot at 400 would be much easier at 8X vs 4X, but both would work.

PB

[Furbyballer]

I have 2 atacrs and I run one on my centurion 12.5 and one on my hodge 14.5. At Buck Doyle's class in utah I took my 14.5 hodge out to 800 yds on 12in steel. It was a slight stretch because I wanted slightly more magnification to range better, but i made about 50% hits with imi 77 grain (20 mph cross canyon winds). I also like the atacr on my 12.5 because the 1x is so flat and that 12.5 shoots out to 600 pretty easily for me and I appreciate the extra magnification.

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[Vegasshooter]

I have both. I’m running the NX8 on my Noveske Afghan 14.5. At 17oz, 1-8, FFP, daylight illum, it is, in my opinion, THE ULTIMATE AR-15 scope. I know things like ultimate, best, greatest, etc get thrown around often. I’ve used most of the 1-6 and 1-8’s on the market. I believe, for putting bullets on bad people, from CQB to the limits of 5.56, the NX8 is THE HEAT.
My ATACR does double duty. It goes from my Lancer DMR 18” AR-15 to my KAC ACC .308. I feel like it is a little bit overkill on a small frame, not crazy so, but on a small frame, I believe it does best on a 18”-20” rifle, or where it REALLY shines is on a .308 DMR rifle.
I love both scopes. I just think the NX8 is so good as a Lightweight, combat capable optic, the ATACR is better used on more gun. Make no mistake though, either one is fantastic. The NX8 could absolutely do duty as a DMR scope on a .308 gasser.

[BallisticHarmony]

I have both. I’m running the NX8 on my Noveske Afghan 14.5. At 17oz, 1-8, FFP, daylight illum, it is, in my opinion, THE ULTIMATE AR-15 scope. I know things like ultimate, best, greatest, etc get thrown around often. I’ve used most of the 1-6 and 1-8’s on the market. I believe, for putting bullets on bad people, from CQB to the limits of 5.56, the NX8 is THE HEAT.
My ATACR does double duty. It goes from my Lancer DMR 18” AR-15 to my KAC ACC .308. I feel like it is a little bit overkill on a small frame, not crazy so, but on a small frame, I believe it does best on a 18”-20” rifle, or where it REALLY shines is on a .308 DMR rifle.
I love both scopes. I just think the NX8 is so good as a Lightweight, combat capable optic, the ATACR is better used on more gun. Make no mistake though, either one is fantastic. The NX8 could absolutely do duty as a DMR scope on a .308 gasser.

That’s great insight. So you don’t feel like the NX8’s glass or 30mm light transmission are hindrances?

[Vegasshooter]

I don’t feel like the NX8 has many shortcomings. I genuinely think, for the $$, it’s the best scope out there. I mean that. I have both because I live as a LEO instructor. I shoot every single day. I teach LPV, and scoped rifle classes. If it weren’t for that, I might not have gone for the ATACR 1-8. The NX8 is that good. There is an upper 2% that would even notice what the ATACR offers over the NX8. Its almost just a business expense to me to justify the difference. Literally IF you’re shooting daily, or a couple times a week, and IF you’re pushing shots out to 600-800yds, you will see a difference. Don’t get me wrong, I LOVE the ATACR, and if it was the only LPV I owned, I’d be happy, BUT the NX8 is 90% of the ATACR for $1000 less $$. In the end, is the juice worth the squeeze?? I can’t answer for you, but for many folks, on any kind of a budget, it wouldn’t be.

I don’t want this to sound like I dislike the ATACR, quite the opposite. When I got it, I was blown away. It’s just that at this level, the gains vs $$ spent become very small.

[Mr. Goodtimes]

14.88 is the ideal barrel length for just about anything.


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[Eurodriver]

14.88 is the ideal barrel length for just about anything.


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I like 15.125. Better equivalencies of flight duration due to harmonic twisting of the barrel flutes.