You get what you pay for and thats ok - Lyman Electronic Digital Trigger Pull Gauge

I purchases this to back up my spring type trigger weight scale. I do ten with spring scale and average. then ten with digital. and average. then average both. they are very close . be sure to use a trigger hand cartridge tester so you are not dry firing it in your lower. you can buy them at a few sights. I think Geissillee has them and Larue and others.if you dont have one just pad the face of your lower with close cell foam so hammee does not mash against front of pocket. don't test with upper installed. put lower in a sturdy vise block preferably an adjustable vise block that you can tighten inside mag well.Like Real Avid makes.