#1 an AR-15 is NOT an assault rifle. The "AR stands for Armalite, the designing company.
#2 Trigger pulls are not measured in inches, they are measured in pounds and ounces. A typical AR-15 will have a trigger weight of 4 - 8 pounds.
This kind of question for a first post raises everyones red flags. Sounds like a question from an anti-gun troll or civil attorney.
In either case I am closing this thread down. If you want to introduce yourself and participate in the discussions here, you can gain some credibility and ask such questions in the future.
In life, strive to take the high road....It offers a better field of fire.
"Robo is right" Fuzzball