So I finally ordered the upper assembly to complete my AR build that's been on hiatus for a couple of years. I'm torn between a magnified optic such as an ACOG or something else, such as a reflex.

Pros? Cons? Opinions? Let's hear it.

I prefer regular scopes, guess cause I prefer longer shooting. I put the Nikon M223 scope on my AR. 1x-4x is about perfect to me on 556/223.

I do need a better and more magnification scope on my 10/22 though.

I'm not sure how much long range I'll be doing with a 16" mid-length upper or even how accurate it would be. I guess there's only one way to find out. I should really turn this into an AR build thread.

Might as well.

Annnnd changed.

I've been going over some build sheets on AR15.com and have watched a few videos. It looks like picking up the vise block is definitely the way to go since it will be like giving myself a third hand to help with the build.

I own scopes (two Nikons ballistic recticle for 223) , AIMpoint PROs (two) Aimpoint Comp (one) and Eotech (two 512 and one 517).

I've shot approx 25000+ rounds out of various AR15s in the last 3 years mostly in high end carbine courses and small unit tactics courses... this was mostly w/ lanes w/ popup targets hidden in terrain....in any weather... and often in the rain , in snow at 19F mountains or at in the sun at 110F.

This is my experience:

Reflex all the way.
Its faster and more accurate.

the vast majority of engagements take place under 100m.
An traditional magnified optic even the nicer newer ones you still need to maintain proper cheekweld but not with a HWS.

The ACOG is nice and LOVE that Chevron reticle, but it costs as much as an entire nice rifle AND its slower at the all important closer ranges even if you train yourself to use it w/ 2 eyes despite one side being 4x magnified (and this DOES take significant training more than most civilian users are willing to spend the ammo on).

In an AO with mostly long ranges, like the african veldt or a rural midwestern AO, or a mountaneous AO w/o Trees a magnified optic like a traditional scope or an ACOG rules.

But in any other AO a holographic weapons sight reflex sight is superior.
(Bin Laden by the way was shot with a HWS , EOtech. Not every HWS is an Eotech but every Eotech is a HWS )

There has been a lot of bad press on the EOtechs lately , like they "lose zero" if you go from 120F down to -20F etc.. But who does that w/o rezero?? e
and with these huge temperature swings air density and ammo temnp etc would force u to re zero anyway.

A true laser projection based HWS like an EOtech with a 1 MOA dot in the middle and the 65 MOA ring simply performs better as a SIGHT even if a LED based redot will always be more robust due to simpler technology and have more battery life.

But if all we cared about was battery life and robustness we would stick with Irons right?

Are AIMpoint PROS more robust? Yes, they take robustness to a ridiculous level, but the 2 MOA dot is too larger for longer shots and the absence of the 65 MOS reticle makes short range shooting harder.

Also a civilian 1st defender you wont have a team to pick up shots you were too slow for or simply missed so you NEED every performance enhancing trick you can get .

My primary sight EoTech 512 has never let me down...... to me that means its robust enough while delivering great performance and doesnt force me into perfect cheekweld like a straight optic would.
It went out of zero only once in 3 years and this was after a move ( likely strongly bumped)

PS: The most affordable sights that are professional grade are AIMpoint PRO/ACO and Eotech 512 at approx 400 USD (MSRP is $420-430 for both,.... have seen sales as low as $360 on both YMMV)

I tried some cheaper sights but none could be relied on to make it through a 3 day Carbine weekend under realistic conditions.

So professional grade sights IMHO start with those 2 and then go up.