Don, Hi and welcome to the forum.
A bull barrel is belled at the end as so it will lock up with the slide without the need for a barrel bushing.
A tactical coned barrel has a cone on the end of the barrel that locks up with the slide and it will be squared to match the contour of the slide. You can see an example of a coned barrel on Wilson Combats web site or possibly one of the forum members may have one that they can post a picture of.
A ramped barrel is just that as it will have a feed ramp machined into the bottom of the barrel. An example of this is a Baretta barrel. The ramped barrel fits into the frame where the feed ramp is on a 1911.
On the 1911 pattern pistol the barrels are throated and polished and the feed ramp on the frame is polished also.
Hope this answers your question and I am sure someone else on the site can go into the subject in more detail.
Again, welcome to the forum. It is full of information and everyone helps as they can. I really get alot of info just reading the posts and the answers to them from the smiths and other knowledgable forum members.
<font size=-1>[ This Message was edited by: Duke on 2001-10-30 17:53 ]</font>
The very best thing you can do for yourself in your quest for understanding of the 1911 is to get the two volume set of paper back books by Kuhnhausen. Most all of your questions and then some are answered in there. You can get them from Brownells.
Bull Barrel = Fat barrel
Cone barrel = tapered at front
Ramped Barrel= feed ramp completely integral to barrel, no feed ramp in frame.