YOU'RE IN LUCK!
It's an election year. WAIT what does that have to do with target shooting, Dave?
So two days AFTER election day is TARGET STAND DAY..... You have to check your local jurisdictions but, most states require that election signs posted along the public right-of-way must be removed by the candidates within 24-48 hours after the polls close. BUT THEY DON'T in many cases. What this means is that after the legal time period, the signs posted along the roadway (NOT in somebody's yard) must disappear, and you can help yourself.
SOME are the weaker H shape, and you don't want those. Look for the ones that are shaped like a ridge pole and two upright poles... П ..., These tend to hold the bigger signs and are much more sturdy, and in fact, will hold a 6" steel plate suspended from above. We have polling places at our schools, so often the school grounds folks gather up those, BUT they don't go beyond school property to do so, and that's where I score mine.
You can hang clay pigeons, or make your own reactive targets from Ship's Biscuit dough to hang from these as well.
I like AR-500 steel plates, since when I bought mine they were pretty inexpensive, and with soft lead BP projectiles they will last forever. Mine were 1/2" thick and IF one also might shoot something modern and high powered, that would be the way to go, otherwise 3/8" AR-500 is fine for just BP.
Boiler plate is also good for the guys cutting out their own reactive "clang" targets. Other steels often don't work well, and cast iron, like an old griddle, nah, a .530 round ball will grease right through something like that...
LD