I was able to attend a coin show down in Las Vegas a few weeks back and one of the coins I picked up was a Franklin half dollar. This coin was produced by the US Mint from 1948-1963.
The Franklin half is know for it's notoriously soft strike on the reverse and, as a result, only a small percentage of these coins have what is know as FBL - full bell lines - on the Liberty Bell.
FBL is a designation used to describe a Franklin half that has complete bell lines across the bottom of the bell. The Liberty Bell on the reverse consists of two sets of bell lines, an upper set of three lines and lower set of two lines. Most collectors today, as well as PCGS and CAC, only consider the lower set when determining whether a Franklin is FBL or not.
Here is a short article from PCGS explaining FBL with pictures
I picked up a raw (ungraded) Franklin half dollar that the dealer claims has full bell lines. I did not have a loupe at the show however I was able to give it to 
However after taking some snaps today I am not so sure this would be considered to have full bell lines.
Hard to get a great picture but I think the bell lines are missing just to the left of the clapper (the inside piece that swings and rings the bell).
The detail on this coin is awesome though. You can see the words printed on the top of the bell as well as some of the wood grain on the wood piece the bell is hung from. The eagle on the right looks decent too.
