I'm curious about methods of well point installation being used nowadays. I never paid them much attention, when they were popular, a generation ago in this area, when a regional drought sent homeowners in search of ground water to keep their lawns green. Most of them seemed to be installed with simple drop-weight rigs. I assume there was a drive cap atop the pipe being driven, with the vent hole enlarged, if the drop weight had a alignment rod projecting from its bottom.
I know that augering would be preferred over pounding in well points, so the soil could be examined, although most of the likely sources I see are in thick layers of gravelly sand, courtesy of the moraines, from the last ice age. In those, I could pound a point, and not concern myself too much with the soil.
What I am wondering about, though, is whether a point-pounder has to worry about the pipe he'd use on a point installation. Most of the galvanized pipe I see is rolled and seam-welded. I could swear it's lighter than the old stuff. I've read one thread about a point pounder discovering the pipe had bowed outward from the impact. That would be in keeping with my misgivings about the modern pipe. I suppose one could use sch 80 pipe.
I've seen one machine that looked like it could do some serious point pounding. It was designed to raise and drop a hollow cylindrical weight, to strike a steel disk laid atop the drive coupling, with the pipe threaded into the top of the coupling keeping the drop weight aligned. I think the machine was for getting soil samples near highway construction, since it could also hammer a point back out of the ground, if another drive coupling and steel disc was set in place above the drop weight. If I were to create a point-pounding rig, I might use that machine as a model.