That's what I'm looking for.  Now, how do I get there.

Right now I'm running the standard A2 front sight with an Ashley Outdoor (XS) same plane rear aperture.  The AO/XS same plane rear ap is just a bit large.  Same with the standard A2 front sight post (too wide) on a 16" carbine.

I'd like a little more precise sight picture with the irons, but don't want to go with hooded apertures, etc.  The standard 20" sight picture should work just fine.  The problem is duplicating them on a 16" carbine with the same plane rear aperture.

1.  What front sight mimics the 20" sight picture on a 16" carbine?

Here's where I've started:
www.bushmaster.com/shopping/dcm/9349056cg52.asp

Will any of these works and are there any other options out there?  What width do I need?

2.  How do I get the 20" rear aperture specs in a same plane unit?

Here is what I'm currently looking at:
www.accuracyspeaks.com/parts.htm  (Apparently they'll cut these per your specs.)

4. .052 X .059 Rear Aperture: Uses the M-14NM sight sizes, allows the same zero with either aperture. 5. .040 X .040 Rear Aperture: Undersized to allow redrilling to custom diameters.

Obviously I'll have to measure the A2 apertures, but that pretty well known.  Heck, the AS guys could probably give the specs off the top of their heads.

Are there any other options that I'm missing?

TIA

EIDTED to add quotes re: AS rear apertures.

DPMS makes a narrower front sight post that will give you the same width as a 20" sight picture on a shorty sight-radius. Not sure of the width though... John at K2 Sports has them and is a site sponsor (has a forum here). That is where I bought mine.

Replace the standard carbine 16" barrel with a 16" Dissapator barrel.

Note when you go to the XS same plane rear sight the aperture is LARGER than the standard A2 aperture.

If you want to keep the same width sight/aperture size relationship then you'll need a thicker front sight.

Thanks for the heads up.  I'll post something there.

I have too much invested in the carbine sized system right now to move to a Dissapator setup.  If I were to get another upper, it would probably be a 20".

I'm aware that the AO/XS same plane rear aperture is larger than the A2.  I prefer the A2 size rear apertures, but live with the larger AO/XS simply because the benefits of the same plane outweighs the slightly larger apertures.

And I don't want a larger front sight post.  The whole point of this is to get back to a 20" A2 sight picture, albeit on a 16" and with a same plane rear aperture.  I'm using the 50/200 Improved Battlesight Zero.

I'll probably just try a smaller front sight post and see how it works with the AO/XS same plane rear apertures.

Thanks.

EDITED to add that if anyone can tell me the size of front sight post I need to accomplish this, it would be much appreciated.