I also do not think the big ones were weighted. The poppers have a little bit of weight you can see on the bottom. I've never cut one open yet though. Don't have one that is enough of a beater.
The big ones don't cast very well I have found. My grandfather however caught a 60 lb'er on a blue goo goo swimmer off scituate many years ago, so they do cast well enough to catch fish.
I've caught a good amount of bluefish on the little 4" swimmers. They hold up pretty well I think with the screw eyes and being made out of a softer wood.
Here is a link to some pics I posted a while back.
http://www.striped-bass.com/Stripert...ad.php?t=30022
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