I'm usually delighted when I see a new guy at the range with a single shot.   

This one was a Ruger #1 with some sort of candy apple red buttstock, maybe more plastic than wood.  It had an ultra-modern scope with all manner of dials and controls, a pretty big yellowish forearm, up snug against the action, and maybe a bipod.  The thing had a bare metal barrel that looked real skinny and kinda too short, maybe 20 inches. I think I've seen sturdier barrels on run-of-the-mill Stevens Crackshots.  There was a muzzle brake or at least a bunch of ports milled or drilled into the end of that whippy barrel.   

He was shooting from the bench on the 100-yard range, aiming at pretty challenging targets. But he wasn't having anything in the way of good results.  I looked through my spotting scope and didn't see any touching bullet holes.  The shooter was muttering between shots a good bit.

The blast from that thing hurt my ears.  After a few shots, I just went to the parking lot and sat in my car, waited until he was done.   

When he got done, I asked him what caliber it was.  He told me it was an Ackley Improved .223.  Good grief!

We all know that there are single shots but then there are single shots.