A few observations from 40+ years of reloading shotshells.
First, you can load any variation of shot size and amount that will work in any gauge. You just have to get good load data and the proper components. That flexibility allows you to fit a load for any intended purpose. I've been loading 1 ounce loads for the last ten years. Every 8 shells, you geat a free shell! Lighter recoil, less powder, cheaper wads, all pay off.
Second, you can load BETTER loads than the econo,( cheap), promo loads that everybody brings up as a reason to NOT bother reloading shotshells. Spending the extra for the hard magnum shot pays dividends in pattern quality. Time spent shooting patterns pays off in being able to make better shells than even the high priced premium ammo.
Third, it's not how long can you possibly load that empty, it's how long you can load that empty hull so it works like it should. Or in other words, how long will the ballistics stay where they should be? The crimp starts to tire out the first time it's reloaded. It gets weaker each time it's loaded. A weaker crimp,(speaking of the force required for it to open), results in a lower velocity. I did a test using the same 5 AA shells that started as once fired empties. I was working at a gunshop that had a progressive loader,(apex), set up for demo purposes. Also a test range in back with a chrono set up. The five shells were fired, the velocities recorded, then averaged. The drop from once fired to the last test at five reloadings was 150 FPS! That's enough to cause a miss at a hard right/left at trap, or a crossing shot at sporting clays. You COULD allow for that by slightly increasing the powder charge, but there goes the cost per shell.
Forth, re-claimed shot or something somebody made by dropping hot lead into water is a crap shoot. Re-claimed shot is NEVER round! It's all dented up, will get worse when fired again. It's like shooting square shot! The patterns will be terrible. Missed targets may be blamed on poor form, not enough lead, or even the shotgun. When it's actually blown patterns caused by deformed shot. Unknown alloys melted and dropped into water will usually be too soft, and will not be very round. Shot has to be dropped from at least 50 feet, to allow it to form a sphere. Dropping it a couple feet forms a teardrop shaped pellet.
