Armalite Carbine Flat top conversion

[HandgunGeezer]

I hane a Armalite Carbine with the A2 style 'carry handle' upper receiver. I bought this rifle in 1990 before the flat top receivers were common. I want to change the upper to the A4 type receiver, but want to know if I change just the upper and use my original bolt, carrier and barrel, will I have to worry about headspace problems. I want this to be a simple swap if possible.

Thanks for any help.

[gunman42782]

Nope.  Should not be a problem at all.  As long as you use the same bolt and barrel everything should be fine. 

[Bidah]

Not a problem.

-Bidah