I swapped out the sights today on my duty gun and decided to take a picture of the S&W Performance Center striker block (circa 2009) and the Apex Tactical USB which will be going into my 40C. My duty gun has the Pistol Action Package performed on it.
Apex on the left, PC on the right. You can sort of see the profile difference. The striker block spring used on the PC Action Package is stiffer as well. Not sure if it's stock rating or not. I haven't torn down my 40C to compare.
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