The textbook safe distance to shooting steel is 30 ft (10 yards) with a pistol (AR500 grade steel).
Now if you are talking about rifles then it's 100 yards.
So, you'll find clubs that will allow closer. There are target designs that will be shot at angle which would reduce and if using frangible ammo will also reduce the distances.
Cowboys shoot closer since they are using lead and also lower loads.
Each club may have their own but overall for just gravity type plates it's 30 feet.
"Shoot Safetly, Shoot Often and Share Your Sport." Jim Scoutten, Shooting USA
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