Oh come on nobody is going to miss a target by 20 feet with a rifle a 100 m.
On the other hand it's not a good comparison. Over that sort of distance a rifle bullet is practically instantaneous.
Slingers see the missile leave the sling and can point out whereabouts it's going to hit - so the observer can step the other way while looking at the area of impact (whihc is what we did). Obviously this is not possible with a rifle.
And judging by most of the slingers on this forum - if I'm stood anywhere near the 200 or 250 yard markers there are only going to be a very small number of missiles coming anything like my way anyway
It is easier to see something landing in front of you.
So it's pretty safe.
There's a phrase 'who wants to live forever ?'
I do
But that doesn't mean I have to live in a coddled ball of special safety regulations
C_A, my man, it is a violation of EVERY rule of firearms safety to be in front of the firing line when the range is "hot." Repeated violations will get you kicked out of most US gun clubs. Accidental (read "stupid") discharges happen; bullets bounce; a rock struck by a .308 suddenly turns into a fragmentation grenade. Sorry to be hard-nosed, but that's the way I was taught and I believe in it. I couldn't believe it one day at the range when I was preparing to pepper a 100 meter target with my 10-.22 and something blue appeared at the edge of my scope. I looked, and this son of a mule was walking downrange without even asking if the range could go "cold." I got his car tag number and reported him to the range master. They had some wall-to-wall counceling and it never happened again.