MBUS Sights, Cowitnessing optics, red dots and magnification
If you are unsure of any of those questions when doing your next AR15 build, you need to spend a few days on youtube.com and learn about each individual trade off and asset. I had to force myself several years ago when I was working on a new M4 selection, that I wanted a close quarters optic that gave me speed and a wide field of view. I started out with a Bushmaster XM15E2 which is as basic as you can get with an AR15. No muzzle brake, just two apertures to choose from and with the right kind of ammo for a 1-9 barrel twist, getting MOA is easy. That was back in the day of carry handle ACOGS and heavy barrels. Now the trend has been towards lighter and stronger.
I always felt that the AR15 was a great training tool and even youth can learn marksmenship on it, which in my opinion kind of gets lost when you teach with a scoped rifle. I have taken some of Ruger 10/22 out with red dots on them, but it’s nice to use the Trijicon RMR sights for sale that we get in and let kids shoot balloons and just have fun. If engagements on targets are under 50yds, iron iron sights or red dots are just fine. Some law enforcement officers want some type of magnification even if its just a pair of compact binoculars. It amazed at the number of people that still revert back to those, but sometimes you need it and sometimes you don’t. If you got the money, there are some nice multitask combat optics from Trijicon that make good use of magnification and red dots.