I have a LaRue MBT in my service rifle and the other day I happened to check the trigger pull with a mechanical weight tool and it broke around 3 and a quarter to three and a half pounds

So I replaced the trigger spring with the optional heavy trigger spring that comes with the trigger and it's still breaking around three and a half pounds

I called LaRue, explained the situation and the guy is skeptical of what I'm telling him which is understandable. He sent me a new trigger spring & Hammer spring which I just installed and the trigger is still breaking around 3 lb 13 Oz

I had asked him if it's possible I have worn out the trigger and he said unlikely because they're made of tool steel

So what am I doing wrong?

ETA I swapped the trigger for another brand new LaRue MBT and this one's breaking around 3.4 lb with the Standard Spring. This is an 80% lower I finished. Could it be a misalignment between the trigger and Hammer that is lessening the pull weight?

ETA I installed my original trigger in a brand new Factory lower and it's breaking around three and a half pounds

Not really sure I'm seeing a problem here, unless your thinking it is too light for YOU. There are several brands like CMC and others that sell 3.5 pound triggers with the pull weight considered an ASSET. As long as the hammer and trigger contact surfaces are intact and not damaged, not seeing an issue.

Trigger pull has to be a minimum of 4.5 pounds to compete in service rifle

Guess I have to poop can my Rock River two stage that goes at 1-1/2 pounds.  Damn accurate though

Okay, fair enough. Its been about 18 years since I shot a service rifle match.

Are you sure the trigger pull gauge is working correctly?

Have you tested any other firearms that have a heavy pull?

I tested my son's service rifle w/ a geissele trigger and it broke right at 4.5lbs.  LaRue told me the handhelds are notoriously inaccurate and offered to have me send my trigger in for testing on their equipment.