That tape measure is a good idea if it'll work, but lot's of times one size won't fit all, and that is why in my opinion you can't beat those steel feeler gauges from the auto parts store.
They are in various thicknesses and about the right width, and when you find the size that fits you can get at least two shims from one gauge strip.
What I do is using a small diameter screw driver I place the strip between my thumb and the screw driver and draw it with a pulling motion across the screwdriver applying pressure with my thumb which causes the strip to take on a curl that with more pressure applied after several pulls will form a tight curl.
Then take the curled strip and place it over the hinge pin on the receiver where it wraps tightly around it, and mark it where the two ends overlap together, and cut it there so they don't overlap, and you can use your wifes scissors for this but don't tell her what you did, and it also doesn't have to be exact.
Then where the shim now comes together, using some needle nose pliers grabbing maybe a 1/16th" or less, turn the very ends of the curled shim back 90* upward, and this will work as sort of a stop once the barrel is seated on the shim and pin that will keep the shim from turning on the pin as you open and close the action. Trust me, it works!
Be warned though, my method won't work with a really thick shim unless you have very powerful fingers trying to curl that thick butter knife thick shim.
