In search of... The Perfect Projectile #2

I just may have found it.  The perfect projectile.  A student of mine somehow acquired this polished piece of steel.  It weighs just under a pound, is as smooth as silk.  It's perfect save two small details which are revealed in the fact that I haven't slung it yet.  Here's why:  1.  I'm afraid to lose it as it would certainly go farther than anything I've ever thrown. 2.  I'm a bit afraid of what it might do. I found an academic paper on slinging recently that had calculated the terminal velocity for sling projectiles on level ground at 128 ft/sec...which translates to...87 mph... which seems low, I'll have to read it more carefully, but in any case, I personally am not interested in the a fore mentioned ball of steel hitting anything except a large pile of dirt wherein which I can find it... and not be found guilty of reckless endangerment.  So the only major problem with this projectile?...It's too nice, too expensive, too rare... It'd be like having a vintage Porche 911, who'd wanna drive it?  Just a tad too perfect...

Back to Perfect Projectile #1

slinging steel...what else?