Best source of lead shot?

From the business end of a Mossberg 500!

Check your local shooting supply store, they should have it, Dick's would as well. Get smallish shot, typically the higher the number the smaller the shot, #8 or better would be my recomendation, thus occupying more of the space and displacing more of the air. Select shooting stores offer lead "dust" shot, which is super cheap and probably the way to go if you can find it. Good luck.

bonjo (is that, like, a banjo played between your knees?) ;o): tireguy's right re: the best sources for lead shot. i'd suggest you NOT use lead shot alone, however, to fill your stands. a 50/50 mix of lead shot (i prefer #8-#12) and high-quality silica sand provides better damping. and it's cheaper to use such a mixture. my tt stand is loaded with 250 lbs. of lead shot/sand; don't know what i'd do if i ever sold or replaced it. -cfb

You might want to consider steel shot if you have (or expect) children in your home. Not as heavy but quite a bit safer. Lead dust is a serious health hazard for all ages but expecially the young. The dust is the problem, so be sure to seal all the openings after you get through.