Tide,
I’d have to agree with Carolina Boy. I don’t think it is necessarily the 21’ that is the biggest risk. It is more of the single engine and lack of radar that would worry me at night. There are many things that probably won’t happen that definitely could happen when you’re out there, especially this time of year when storms pop up without much warning. Not having the ability to see how far away/how large these storms are and/or not having the ability to outrun one of these storms is in my opinion a chance not worth taking.
If you really want to catch a sword, take the safe bet. Trailer your boat down to Ft. Lauderdale, Florida (8-9 hours). Put in and go out to about 1,300 ft of water (straight out 15 miles). Make one drift straight north. You’ll have a great chance of catching some swords. In addition, it’ll be a much safer bet and there will be plenty of other boats out there. Also, check out swordfishingcentral.com for some other info on catching swords.
If you do take the chance and go offshore here in Charleston, make sure you at least have an EPIRB. You can rent one if you do not want to make the purchase. Your VHF will have some problems reaching help at 60+ miles during bad weather.
Good luck
33’ Hydra-Sport