I have 3 B & K 465 crt testers. All 3 will test the same tube different. Is there a way you check the tester? Calibrate it maybe? Thanks for your help.

Look around sor the service manual for it. Some tester repair manuals have calibration proceedures in them.

I have a 465 and the manual.
The only adjustment in the manual is a 20K pot that calibrates the meter using the heater voltage while monitoring the voltage with a known good voltmeter. Everything else depends on the accuracy of the resistors. However from some further testing I've done, the meter emission "GOOD/BAD" corresponds to 300 uA with the meter switch set to normal, and 40 uA with the meter switch set to sensitive. I used a 1.5M pot in series with a sensitive ammeter across pins 10 and 11. Those pins will have about 300V across them with G2 at max.