Hi Frank,
Normally, you will be around the 25 lb mark when you are between 42 and 43" waterlines which are class required. For a 95 hull, it takes almost exactly (depending on hull) 2 lbs of ballast to go from the 42 to the 43. Most guys have this in seperate pieces which they can use to adjust their boat for particular winds. I would say that you probably won't get much below 23 lbs and still be able to reach a 42" waterline.
I am guessing that this is a pre- 95 hull standard (not sure if that was what the 91 was about) but in the case of such a hull they were typically thinner in the keel area than the 95, and could be quite a bit thinner in some instances. Back when that boat was made, there was a 26.5 lbs limitation on displacement, but I don't see that rule in the current rules... probably because you could not reach that weight without hitting the max waterline of 43.
The lead shot... I HOPE is not buckshot as that would be almost marble sized... hopefully birdshot.. most guys used #9 shot back in the old days (I did) and it is the least effect method of ballasting the boat. Sorry. I would offer some suggestion of how to change it out... but I don't know of a way that would be easy enough to even mention. I would sail the boat as is, and if you were wanting to get serious racing with EC-12 think about another boat. That one will give good service and do fine in most instances... might even be right up there in the lighter air races, but as the winds pick up... well.. it's still a nice boat.
The EC-12 WILL FLOAT in your standard bath tub... but it's a bitch to hide under the sink when Mom tells you to get out. Some lucky guys even have enough headroom to put the rig up. One pound is a fairly common weight for a complete rig, you can get them lighter but for your purposes it will at least answer some questions for you.
Good Luck with it,
LL
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