I found the Timney springs to be to light in my micro hunter. The micro hunter is not the same trigger as the other A bolts, so be carefull ordering a new trigger. I found a spring, lighter than factory, heavier than the Timneys, to be right. I did see a trigger for the Micro hunter somewhere, maybe Brownells, not cheap though, around $100.00. I'm real happy with mine and the different spring.