Recommendations on how many rounds to run through before my first cleaning? Have read a bunch of varying opinions and wanted to get some actual feedback.

Thanks in advance.

You should have cleaned it before the first one.

This. For new ARs, factory or builds, I tear them down, clean everything, and then properly lube everything.

From there, once I get it zeroed...I’ll tear it down again to look for any concerning wear and if all is good, slap it back together.

If something is going to sit in the safe for a while, it gets a cleaning and lubing...otherwise if it’s going to be in my range/class rotation for a bit, it generally only gets a full cleaning as needed...which can be quite a while with today’s lubricants.

I clean and inspect a new rifle before firing.
Then, I lube liberally, run it wet for 300-500 rounds.
I then clean, inspect, lube normally and lightly clean after shooting.

i clean things as i assemble the rifle then again when it starts to run sluggish, maybe a few drops of oil in between

they are tools not safe queens

i also run everything suppressed

Clean/inspect upon receipt.  

No schedule after that personally.

+1

After cleaning all of the preservative off and properly lubricating the thing, some regular cleaning should be performed.  Reasons why:

1) A clean properly lubricated rifle will always be more reliable than a dirty one.
2) A clean properly lubricated rifle will always wear less than an dirty one.
And, most importantly:
3) You cannot inspect parts unless you disassemble, clean, and look at them.

Cracked bolts are a thing, it does happen.  It is not a common as the internet leads you to believe, but it does happen, you should clean them and look at them regularly.

"But you can't see a crack." - Yes, you can. when the crack first starts, you can usually only see it through fluorescent penetrant inspection, but it will grow and become visible under medium magnification.

"If you can see it, it's too late." -  No, The Army has done many endurance tests of more than 6,000 rounds on many hundreds of M16s and M4s throughout the years, and some do turn up cracked bolt lugs during the course of the test.  Usually, the bolt is returned to service to see if and/or when it actually fails, rarely to they shed a lug before 10,000 rounds (if ever before the test conclusion).

"Isn't that dangerous?"  Not really.  In a test where bolt lugs were intentionally removed, a bolt with only two lugs (the bottom two, so it would feed), withstood 6 rounds before jamming in the closed position, and bolts with five lugs (missing the two flanking the extractor) when for nearly 1,000 rounds before the headspace exceeded the field gauge maximum, it did not fail catastrophically.

"I replace my bolt every 5,000 rounds, because that the life of the bolt."  Well, how often you replace parts is up to you, and how deep your pockets are.  But, the Army's average life of a bolt is well in excess of 5,000 rounds, some bolts do see cracks at 5,000 round, many more do not.  So, if you clean and inspect your rifle at least every 1,000 round you should catch and problem before it becomes a safety issue.  It doesn't have to be "white-glove inspection" clean, but functionally clean.

And one last thing:
Hopefully, you change the oil and oil filter in your car every 3,000 to 6,000 miles.  The main reason is to remove the old, dirty, abrasive containing oil and replace it with clean oil, doesn't your AR deserve the same consideration?

Why would you change your motor oil so soon?

There is no comparison between motors and rifles.  Your new motor is not still full of chips, cutting oil, and cosmoline.  It has already been thoroughly cleaned and run with new oil.

Clean it the first time, then break in about 500 rounds. You don't -need- to clean it after every range visit, but it's a good practice to have.

Piston system require about 1/4 the amount of maintenance in terms of the amount of parts that need to be cleaned.

My thought is you should clean it after every range session unless you are shooting daily. At the very least you should be passing a snake with some oil on the end or oily patch through the bore every so often. Learn to clean it correctly.

While a lot of folks say don't clean it or clean it only after some number, I would say you really don't know how long these people's rifle last. There are still A1s in service that are used by brand spanking new recruits. Imagine that. Someone with probably 0 fire arm knowledge, they give them this ancient weapon that their grandfather used, and yet, it still functions. Some have new barrels, others still have their original barrels. Of course they're not super accurate but the point still stand: cleaning your weapon makes it last a heck of a long time.

Follow this video and repeat it as often as necessary. When I first got my rifle, I probably disassembled and cleaned it a dozen times before going to the range.

Upon purchasing any new firearm, and in this case an AR, one should clear, disassemble, clean, reassemble, function check and lube.  Routine PMCS (preventative maintenance checks and services) are vital to any weapon system.  If your aren't doing this you are wrong.

100% this.

removed

I do mine every time I shoot it rounds dont matter to me.

I clean after every outing not on round count!

Plus by taking it apart and putting it back together, you've made sure that there are no glaring problems with the gun - no plugged up barrels, no frozen bolts, nothing obviously broken in it.

I figure I cleaned them enough in the army that I won't ever have to clean anymore.    Well I do still spray the barrel down & run a barrel snake through after firing and toss the BCG in some Slip 2K carbon killer & then re-lube as well.  The other stuff I usually only clean if it's visibly dirty.