I have an EA (Essential Arms) preban lower receiver. I am in need of an upper receiver and don't know what kind is compatible with my lower. I tried fitting up a Colt upper but would not fit. Any help would be greatly appreciated.

Try Gunsmoke Enterprises.

http://www.ar15.tv/index.php

He has been around and knows the business. It looks to me that he has started to sell under his own brand too.  He can fix you up, I'm sure of that fact.

Colt wouldn't fit???  Pleas explain what and why. If the Colt upper was a "big hole" early model, it would be loose, but I can't think of any reason other than that for a Colt upper not fitting a properly dimensioned lower.

BTW, you might want to check out other users feelings about the Gunsmoke Enterprises referral. My one experience w/them was fine, but I was just ordering some small action parts.  Other folks have not been happy with what they got from them.

[url]www.rbprecision.com[/url]
Ask for Robert, he's the best, IMHO.

I'm not sure what style of Colt uppper it was but when I put the front pin in it went in fine. When I put the rear pin in, it was a little tight. Then when I pulled back on the charging handle the bolt would stay back. I would have to tap on the side of the rifle to get it to go forward. Just seemed like a tight fit. I contacted Colt a few days ago and they said that a Colt upper would not fit and they had no suggestions for me. Thanks for all the help!!