http://www.hotkey.net.au/~orrs/BismuthArticle/index.htm is a series of articles on how to make nontoxic shot with bismuth.
I do not know if bismuth works well in small shot sizes that might normally be used in small gauge guns, such as 28 gauge. Bismuth is more brittle than lead, we are told, so smaller shot sizes may allow the pellets to break up too much - I do not know. Maybe #7 or #6.5 would work out. Lower density calls for larger pellet size than lead for similar external performance, anyway.
The Ecotungsten shot is sold in #7.5 as the smallest size. Same density as lead, and a little harder. $50 per kilo - 2.2 lb. About $22.75/lb. About $1.42 per ounce. About $1.07 for a 3/4 oz load (28 gauge). Loads with normal lead shot wads, etc. I could stand that cost for hunting, but would not like it for target shooting. The harder NiceShot might pattern better than lead due to increased hardness - have to try to know for sure.
