Sensible answers are accepted but daft ones are much more interesting.
Please note, I don't shoot, have little idea about ammo so technical details don't overwhelm me with them :)


Well when you fire a lot of round pellets like that out of a cannon its called grape shot so obviously grape seeds could be a good way to go?
That might be leaning more towards the non lethal end of the spectrum.
If you had a large enough bore and you wanted to go darkside you could perhaps consider using a duck's face; what could be more terrifying to another duck than to be shot out of the sky by the apparently screaming (quacking?) disembodied face of another duck?
The major advantage of this ammo type is that as long you dont miss and you manage to score a kill shot you will be able to harvest the materials you need for another shot from each duck you shoot down and that my friend is what you call 'sustainability'.
But just incase you actually wanted to be serious, it is my understanding that there is now a technology which allows for the production of a material pretty similar to plastic / functionally very close to plastic which is in fact made of wood and which biodegrades all on its own over whatever much shorter than plastic time frame, that might be suitable assuming it was hard enough and didn't melt or whatever when firing.
It’s an ongoing review of the change from lead to an alternative to say steel.
it’s part of an overall environmental review of lead poisoning in wildlife, also for butchers and supermarkets selling game with lead still inside it.
it’s been going on a while, as @purplepoppy says some estate banned it early.
A lot is down to ballistic properties of any alternative, it’s penetration, the overall cost and impact of the alternative on the environment.
chances are it will not be a full ban, as clays will likely remain lead, also for non food kills.
That's a UK organization. It's been in force a while now and even before that lead was banned on many estates.
Opinion
5Opinion
Bismuth, Tungsten, and Steel.
Technically the "steel" shot is actually soft iron, but it along with biodegradable wad cups are the best option as far as what's readily available.
Bismuth performs most similar to lead, which is theoretically ideal, but is also much more expensive, which is also a problem with the Tungsten-polymer alternative, which additionally leaves plastic in the environment.
here it has been the law for a long time that you cannot use lead shot for waterfowl on federal or state land, as well as for certain types of other birds.
Look up the laws in your state.
Steel has been common for decades, works fine
Using rubber would save more lives.
Some say bismuth is most like lead
The only opinion from girls was selected the Most Helpful Opinion, but you can still contribute by sharing an opinion!
You can also add your opinion below!