Help on Setting up Red Dot Sights

[trextrd]

Okay so lets start by saying I'm not huge gun person so I'm not that "well informed" on how to properly setting up sights other than standard iron sights.
I'm fairly new into the optics game as far setting them up, I've had a few used guns that I've bought but basically already come with a scope (not a red dot) "zero'd in so basically they were ready to go.

Question
Anyway I want to go with a red dot a set up on a AR-15, my main question is do red dot sights need a front iron sight to work or how exactly am I suppose to set them up?
I know it's probably a dumb question to you experienced guys but figured it might be worth the bash.
Please feel free to let me know what else I may need to know about them.

Optic
I was thinking of going with something for beginners like the Bushnell TRS-25. Any other suggestions?

[Kwikvette]

You don't need iron sights to use a red dot with.

If you're concerned about initially zeroing your sight try this;

Remove your upper from your lower and remove your BCG and CH. With that being said, ensure your upper is secure/stable and aim your barrel at your intended target. Now, adjust the windage and elevation on your red dot to place your dot on that same target. Go back and forth between looking down your barrel and your red dot until both are as close as possible.

This has worked very well for me in all my years shooting and setting up optics and within 2-3 shots you should be all set!

Also, don't be the guy to try and zero immediately at 100 yards

[pennys dad]

:-) Great advice. Kwikvette is right.

Using the front sight and reddot is called co-witness. It is a sound practice.
Zero your front sight first (25 or 36 yard zero is perfect). There are two types of co-witness Absolute and Lower 1/3rd.
I will link a great youtube describing both method.
Short answer, I use a lower 1/3rd because it works for me.

[trextrd]

You don't need iron sights to use a red dot with.

If you're concerned about initially zeroing your sight try this;

Remove your upper from your lower and remove your BCG and CH. With that being said, ensure your upper is secure/stable and aim your barrel at your intended target. Now, adjust the windage and elevation on your red dot to place your dot on that same target. Go back and forth between looking down your barrel and your red dot until both are as close as possible.

This has worked very well for me in all my years shooting and setting up optics and within 2-3 shots you should be all set!

Also, don't be the guy to try and zero immediately at 100 yards

Thanks very helpful definetly will be trying this, appreciate your response.

[trextrd]

:-) Great advice. Kwikvette is right.

Using the front sight and reddot is called co-witness. It is a sound practice.
Zero your front sight first (25 or 36 yard zero is perfect). There are two types of co-witness Absolute and Lower 1/3rd.
I will link a great youtube describing both method.
Short answer, I use a lower 1/3rd because it works for me.

Yea I wanted to use the front sight to be a cowitness just because I'm new to seeing threw a red dot sight.
Thanks for the response !