I am building my first AR.
I already bought a pre-ban bushmaster 16" heavy barrel assembly.
Should i buy a flat top or A2 upper.
Let me here the pros and cons.
thanks
UNreal

You can buy a flat-top and have both options.  Mount a det. carry handle or use the flat-top rail.

For your first rifle, you should probably go with a flat top - it will give you more options in terms of optics and iron sights. Later on, if you decide to buy/build more AR's, you can certainly opt for an A1/A2 upper on a KISS-type rifle.

Quoted: You can buy a flat-top and have both options.  Mount a det. carry handle or use the flat-top rail.

+1

Is a detachable carry handle on a flat top  as rugged as  an a2 upper i am building it as a SHTF rifle.

Quoted: Is a detachable carry handle on a flat top  as rugged as  an a2 upper i am building it as a SHTF rifle.

Potentially just as good. All bets are off if you decide to go with a cheap knock-off though. One question that I don't think anybody has asked yet is wehther you plan on using optics with the rifle or just irons?

If you can easily bust a coyote at 100 yards than all i will use are the irons.

The flat-top M16A4/M4-style upper has made the carry handle upper---either M16A1 or M16A2/A3-style---completely obsolete.

The flat-top gives you a vast number of options for mounting iron sights, red-dots, night vision and conventional scopes.  While sacrificing nothing but useless weight.  The detachable carry handle is a result of unthinking military conservatism; there are several excellent iron sights that can be mounted on a flat-top that will be as strong as an 'A1 rear sight and stronger than an 'A2's rear sight.

The A2 gives you one option, the A3 gives you all options.  Sooner or later you will get the A3, so you might as well do it the first time.

the A3 gives you all options

amen

Exactly.  My AR adventures have been such:

1999 - after I got out of the USMC, bought a 20" A2 with AK brake (whoops), to have something just like the M16A2 I had lugged around for nine years.
2001 - got the hankering for a shorter barrel.  Bought a 14.5" with Mini-Y (whoops #2), had it put on my same upper.  Still have the original barrel.  No idea what I'm going to do with it.
2003 - got the hankering for a flat top.  Bought a RRA A3 upper, had the 14.5" barrel put on it.  Still have the A2 upper.  Might sell it, might keep it for a DCM build later.
next week - sending the upper off to ADCO to get the Mini-Y hacked off and replaced with a flash hider.

Bottom line, get a flat top.

It is interesting to note that this article states the carry handle upper to be preferred.  When I first got to arfcom I read that article and it stuck with me.  I also took it seriously.  I got a carry handle upper.   At this point, I would suggest going with the flattop upper also.   That article should be updated IMO.

flat top
you get to exchange btw a detach carry handle or a optic

H/w, a2 is more durable and simpler in my opinion

Here is a new spin on it.
The det. carry handle cost $99

the a2 upper cost $129

it only cost $30 more bucks to get both uppers
is that a good option?

UNreal

another vote for flat top

I guess I'm just old fashioned as I still prefer the A2 for CQB. I prefer the optic mounted on a FF upper rail.

It is amazing how many people switch froman A2 to an A4 upper, then mount an optic on the fore end and attach a big fixed BUIS on the rail. You are basically back where you started with the A2.

I like the solid, always there ruggedness of the A2. If I am in a gun fight and my optic goes down, I DON'T want to be messing around with flip-up thingies.

I prefer the flat top for use on SPR or varmint type rifles scopes with a fixed eye relief.

"get both"

if you want to build an upper on the cheap, you can find some real good deals on A2 uppers(check the EE)

when you have a little more money to spare....maybe you want a target AR or expensive M4, you can get the A3.....


the great thing about ARs.....if you get something and don't like it after a little while you can just sell it and buy something else.

Quoted: I guess I'm just old fashioned as I still prefer the A2 for CQB. I prefer the optic mounted on a FF upper rail. It is amazing how many people switch froman A2 to an A4 upper, then mount an optic on the fore end and attach a big fixed BUIS on the rail. You are basically back where you started with the A2. I like the solid, always there ruggedness of the A2. If I am in a gun fight and my optic goes down, I DON'T want to be messing around with flip-up thingies. I prefer the flat top for use on SPR or varmint type rifles scopes with a fixed eye relief.

The 'A2 sights are anything _but_ "rugged."  I've seen several damaged beyond use by relatively minor falls/drops (off the back of a 5T truck, etc).

The carry handle uppers are an awkward second-best  system.  A fixed BUIS like the Cav Arms or LaRue is going to be better able to stand up to abuse than an 'A2, and shouldn't do any worse than an 'A1 rear sight.  While allowing a better stronger mounting for optics, etc, and not adding useless carry handle weight and bulk.

The chances of an optic going down "in the middle of a gunfight" are wildly exaggerated.  I'm not a fan of most of the folding rear sights simply because they are overly complex for a _backup_ sight, and that means more complexity/fragility, more maintenance and ultimately more _money_ than a simple fixed rear sight.  The few seconds to remove a malfunctioning optic or flip up a folding BUIS aren't going to make any difference in the real world.