Ok. This is the redneck version. I use a featherweight wide gap fishhook (like a 3/0). I put a low weight line on it. Cycle the bolt and stand the rifle facing straight up in my vise. I add a 1/4 oz bell weight to the string and release the full weight on the trigger very slow. Repeat until the trigger breaks. Key is to very gently release the weight so there is not jerk involved. Perfect no. But it was within 1/4 oz with compared to a Lyman of a buddies at the range. Luck, Tim