I'm looking at a Colt "Match Target" flat-top rifle that is postban. I live in VA where there is no longer any AWB restrictions. It appears that unlike my A2 Sporter (Big-hole rifle) the A3 has normal sized pin holes.
Can I drop any upper (physically) on the A3 Colt Lower I'm looking at? If so I'll likely sell my pre-ban A2 for the flattop.
Yes you could drop any small pivot pin hole upper or any large pivot pin hole upper but with an adapter pin on any Match Target lower with small pivot pin hole.
Current production Colt LE models are the same way they have small pivot pin holes.
I have a Colt model MT6601 Match Target HBAR lower that have small pivot pin holes and I dropped in a new Colt M16A2 upper half also with small pivot hole on it and no problems.
I also have a LE model AR6721 carbine which I converted from a two screw type small pivot pin to a M16 type push takedown pin which is also made by Colt.
If you could do it try to keep your A2 for your collection, I sold my first SP-1 and now I always feel bad about it, I wish I didn't sold it.