Laserlyte, makers of the infamous pistol bayonet, have developed a training laser device called the LT-1. The LT-1 is inserted into a pistol barrel and is sound activated by noise from the hammer striking the firing pin/transfer bar. Presumably it also works on striker fired pistols such as Glocks.
It comes supplied with a daylight target which has a reflective coating. When I suggested to the Laserlyte PR person that another person would be needed to spot “hits”, she told me that it is obvious when you hit the reflective target but another person spotting could be useful.
I think this could be very popular with proponents of point shooting – a pistol shooting technique where instincts instead of sights are used to aim.
It comes with adapters to fit pistols in calibers .22 – .50 with a barrel at least 4″ long.
More info here.