I have a 2 stage match trigger on my Anschutz bolt rifle, i find that the take up is a nice prep to the glass rod break of the 2nd stage. It breaks at 1.1lb / 502g. which is .2g over the Bisley trigger weight limit.
Having that light a second stage makes a huge difference for my accuracy and is much more 'responsive' at the brain/nerve impulse/finger movement/trigger release, that i could not go back to a single stage trigger for my offhand precision competitions. The hardware is perfect and leaves no room for the operator to blame the equipment. (unfortunately
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On a semi-auto I'm not sure if the 2 stage would really be utilised as well as it could be because the 1st stage would not really bring any benefit if you are rapid firing, unless you were taking your time between shots and really exploiting both stages of the trigger. I personally love my Anschutz match grade trigger, it has indeed spoilt every other trigger i have shot with.
Saying that, if this is a second rifle then i would definitely give it a go.
PS
Did you sign the petition?