I had been running the apex heavy duty striker. I had also replaced all my springs with the mcarbo lighter springs except one. The combination of the light striker spring and the heavy striker was causing light strikes. Now with this titanium one I am able to run the light striker spring with no failures. If you want one of the best striker fired trigger pulls run the apex trigger and sear with mcarbo springs and striker. I have never came across a better feeling striker fired trigger pull. That says quite a bit because out of the box the 509s trigger is not good in comparison to most.