M4 500m Optic?

[Entropy]

I'm working on a accurized rifle build in 5.56 with a 16" barrel. I'm trying to decide on what optic I should buy. I'm wanting to get into longer ranged shooting, and I know that half of the project will be the rifle, and the other half will be the optic. Most likely I'll be shooting 70gr-80gr loads, and I would like an optic powerful enough to identify and engage a 12" diameter target at 500m. Also, I would like to have a reasonably easy detach mechanism to pull up the BUIS. I'm willing to spend up to $1000. Any recommendations? Thanks.

[shootist~]

For your intended use a quality variable with 10x on the high end would be about the minimum. A 12" plate at 500M is a difficult target for an AR, but possible with an accurate AR and match ammo...and on a calm day. Doing it with a 16" CL barrel will be a challenge. Move up to an 18x18" gong and you can get there with a 4x ACOG.

[IrishDevil]

My rule of thumb is 1x magnification per 100 yards/meters to make easy hits on a torso sized target. So 500m would be 5x magnification. I'm not a really strong distance shooter so I would consider a 12" plate at 500m precision shooting and double up to 10x. For an AR I consider 12x to be the top practical magnification.

$1000 may be a little limiting, if you include a mount in that price. A Larue will run right at $200. I have some time behind a Trijicon Accupoint 2.5-10x56 with mildots and I liked it. Is it a Nightforce or S&B? No, but it is a quality optic. Not sure about current prices or options without checking, but Larue was selling the Triji with mount for about $925.

[sinister]

You have several good, affordable options under $1,000 if you're patient.

TA01B ACOGs (with the 308/7.62 reticle) will give you 4X -- maybe not enough to hit a 12" plate at 500 but an excellent fighting optic.

Leupold 3-9 or 2.5-8 MR/T scopes in a Larue mount are an excellent option, as is a Leupold M3LR. 1.5-5X will be OK, but may not resolve a 12" plate early in the morning or as the sun starts to set.

Trijicon and Nikon are offering some nice scopes.

Nightforces and other premium scopes start over $1K new or used.

[infidelprodigy]

I've used the Leupold 1.5-5X MRT out to 500yds with no issues, but that is on a Larue upper. Like stated above, ammo and upper selection are critical when it comes to small targets at distance with the 5.56mm.

ACOG's are good, but variable power optics are really needed for such precision work. Nightforce & Leupold are my favorites from a quality, experience, and customer support end; but they don't fit everyones budget.

The Accupoints are the sleeper in the optic world. They are fantastic and are a steal at their pricepoints. According to the Trij guys at SHOT, Nightforce makes everything on the Accupoints but the rear end where Trijicon puts in the tritium and other reticle specific things.

For a budget under $1000, get an Accpoint and Larue SPR mount and don't look back.

[Entropy]

Thanks for all the advice. I'm leaning towards the 4x ACOG TA31-CH. I've seen the package sold for about $1k at several stores.

Sinister,
Is there a reason why you recommended the ACOG in .308 when I'm setting up for 5.56?

[shootist~]

I'm not Sinister, but a .308 BDC reticle is a better ballistic match for heavy (75-77 grain) .223/5.56 bullets.

[Entropy]

I'm not Sinister, but a .308 BDC reticle is a better ballistic match for heavy (75-77 grain) .223/5.56 bullets.

Thanks. That was a concern of mine, assuming that the .223/5.56 scope is setup for M855. I guess I'll be looking at scopes for .308 then.

[TehLlama]

I can do 12" target at 500 with a 4x ACOG all day, but a bit more magnification might help more.
The Leupy MR/T 1.5-6x might be a viable option for you, with a Burris PEPR, or LT/ADM SPR mount you'd be completely set.

Within 700m the 175gr .308 ballistics matches 75/77gr extremely well, nothing wrong with that, but I see larger shifts in my cheek weld than a BDC difference is going to make.