We recently were given some of the original AMU M-K II triggers. First impression, we noticed a very significant bend in the trigger spring that gives a heavier first stage trigger pull. We tested the AMU triggers and came up with 3.5 lbs to 4.0 lbs, which influenced our decision to produce a heavy duty (HD) trigger spring for M-K II users. The HD spring weighs in at approximately 3.75 lbs (first stage) which is 1.5 lbs heavier than the G.I. style spring supplied with M-K II triggers. In short, our HD spring will give the user a heavy first stage feel. We will now include the HD spring with all
M-K II models. If you're already using an M-K II trigger and would like one of the HD springs please contact us at
The Wisconsin Trigger Company.