I don't completely understand what you question is here.... so I'll kinda pick your post apart and hopefully somewhere in the mix you'll find an answer you were after.


Which ones? There are a few new loads coming on to the market every year. Mostly though, the ones you may be reading about on the forums are a few years old.


Tungsten based shot has been around for well over a decade.

There are a few new innovations that has helped improve lead based shotshells in the last five or six years.


Reader's Digest version: Tungsten based shot, like steel shot, is much harder than lead shot. Shooting hard types of shot through a fixed choke barrel will infact wear away the choke (more specifically the lip of the choke where it starts to constrict) inside a fixed constriction barrel. It can also lead to barrel bulging or bursting from increased pressures due to overchoking and internal barrel wear (so I read). Most manufacturers have uniformly agreed that shooting tungsten based shot out of a full choked barrel in limited quantities (such as turkey hunting) will cause minor cosmetic rubs in your bore, but will not damage your barrel or firearm. Its high volume shooting where you have to be concerned.

Anytime really. As long as you are NOT hunting migratory waterfowl (ducks and geese) or in an area that requires non-toxic shot for hunting/shooting purposes.


steel?

You can shoot steel shot for any hunting or target purpose (legally, based on non-toxic laws anyway). It is not adviseable to shoot them out of older fixed constriction guns with tight chokes for the reasons I listed above.

copper?

I am unaware of an all copper pellet for shotgunning. Legally I suppose it may be used, though it would be likey as expensive as some of the tungsten based shot and much less effective. Most shot that involves copper uses it to coat a lead pellet in order to decrease pellet deformation as it passes through the choke. Deformed pellets fly in deformed lines which gives you deformed patterns. Round pellets fly much more true, so keeping your pellets round is to your advantage.

Again, see above.

You can use lead in any sound, working firearm. There maybe places you cannot LEGALLY use it, however, and there ARE certain game species you cannot LEGALLY use it on. Again, you'll have to refer to my above rant on why you should not shoot harder shot types through tightly constricted fixed bore guns.


What's your question? Tungsten shot (tungsten based shot) has been around for well over a decade. The reason you can only use lead in older fixed choke barrels is because tungsten (like steel) is much harder than lead and can score your barrel. Moreover, it can cause excessive pressures in certain situations and lead to barrel bursts (so they claim, but I'll buy it).