Here some recommendations based on my experience.
Any of these are top choices....
On the entry level:
- Burris Fulfilled 3-9 with drop comp or E1 reticle. Amazing glass and E1 reticle with elevation and windage for 10mph crosswinds so it is great for holdover.
- Timberline also great. 2-7x32 might be all you need and it is a very good quality picture in a very light and small footprint.
- Redfield with their compensation reticle 2-7 or 3-9 magnification also very clear glass. These are made in the USA backed by Leupold. Also very light which is good for the AR.
- Any entry Nikon like Prostaff, coyote give very nice value for the money.
On the mid level:
- Vortex Viper - Amazing scope for the money. Will do everything you want a scope to do and more. Zero stop available. A bit more than the Nikon.
- Bushnell ELITE 6500 makes some models with amazing magnification ratio and great glass. You have a 2.5-16 with Mildot that gives you huge versatility.
- Nikon Monarch with either BDC or mildot. Reticle is a little coarse but he optics are amazing! 3-9x44 and 4-16x44 are on sale due to the 50's taking over. Amazing clarity and eye play/relieve. Adjustments are true and simple.
-Leupold makes some decent ones and although you pay a bit more for similar they are all build here. Leupold 1.25-4x20 VX-R and 2-7 are great choices for AR.
-Wotac makes a great 4-14x44 wiht the EBP reticle. It is really amazing value for entry to mid level.
On the High end (Expensive End) this is not necessary for any first build obviously but I am mentioning in case someone is looking for a high end scope....
- Ior Valdada, Zeiss, Nightforce, Leupold Mark4. I shot S&B but I do not have one of those. It might come one day but I have plenty for now for any extreme long range work so this is not needed at all. You can only spend so much in expensive toys.
All the scopes above have very decent to superb glass with no chromatic aberration or aspherity that I could appreciate. Some they are more coarse reticle and faster/easier or slower/more complex adjustment but even in the entry level, the reticles map well on the field to what the manufacturer says they do. They do have good warranty and actual support system if you need something.
I personally would stay away from all the $100-200 Chinese scopes although some we might not know if they are done there or not. Better save a bit more and go for the Japanese or Philippines with Japanese glass but preferably always US (of course!) or European whenever we can.
I cannot put a $1.5K dollar glass system in every AR/upper or rifle I have nor this does make any sense anyway so for some M4 systems and "go" carbines I use an entry' small footprint' Burris or Nikon coupled with a simple reliable red dot at 1PM. Since the AR is inherently accurate this covers any requirements for the typical standard Carbine use whether it is tactical or hunting varmints.
In the SAS/SPR systems I use a Monarch or a mid budget Leupold or Vortex. 4-16x50 Monarch or Vortex are my favorites.
Here some illustrations of some combinations....
Timberline very light, small footprint and simple. it works great. Burris = lifetime warranty. I believe I have at least 6 of these.... (close up below)
I am not sure what I have on this one. I think is Bushnell Elite but you see the red dot at 1pm.
Nikon Morach in a 6x45 SPR...
This is another Monarch on top of a piston M4. This is one of my padawans shooting...
This is the close up of a timberline on top of a SU16 with three working sighting systems...
As I said very good combo for my liking in a 'go' system...
Found these great mounts for $20 that work great with the little scope and with a tiny pressure washer do not loose up or loose zero. So save the remaining $160 of the Larue mount toward the glass or something else.
CAn alternate all three sight systems from CBQ even with the scope due to the x2 intial magnification and amazing eye relief all the sway to make the steel go 'dong' at 500 yards.
Small scope...
Bullet comp to 500 yards
Iron sights...
Red dot at 1pm... zeroed at 75 yards...
Thsi is similar setup on top of a russian AK in .308 Winchester...
A simple red dot on top an AK co-hosting the iron sights. Another 'go' system.....
I don't even know which one is this one but probably a bad investment...
I hope this helps with some ideas. Thanks.