I’ll add pin gauges.Re: re: Gauges
Pretty broad order.
Start with a good set of outside micrometers, inside micrometers, a couple dial calipers, a set of gauge blocks, a tapered thickness gauge, a set of thread gauges, and a Vernier protractor. These are generic machinist's tools, and for a decent set, you're already in for well over a thousand bucks; for a top-shelf set, like B&S or Starrett, it's several thousand.
Now add gunsmith specific tools, like a full set of headspace gauges, dummy cartridges, and assorted other go/no-go gauges, and you've got a whole bunch invested.
For only one model of pistol in only one caliber, you could cut the list way down, but you'd still be in for several hundred dollars. Then, you'd still need to get the specs and tolerances on each part from the factory... otherwise, after you've measured a part, how you gonna know if it's good or bad?