M*CARBO Brotherhood

FN509 Tactical spring kit

Just complete the MCarbo spring install earlier this week and went to the range this morning. Although the trigger pull is drastically improved, I now am experiencing light primer strikes. Actually 10 light strikes out of a 100. Got home contacted MCarbo (waiting a response, it’s Saturday) but I did take a second look at the install and it all seems correct. Hoping I get this resolved quickly…
Larry

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General resolution is likely restoring some selection of factory springs to find a balance that reliably ignites primers.

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out of curiosity what ammo you running thru it? and how many rounds been run through the gun total?

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I am running 115gr PMC, basically all I have used since purchasing the gun. I have about 500 rounds through the gun, 400 of that before making the spring changes and have not had any problems or light strikes.

In addition, I replaced the striker after the First 100 rounds with the APEX Striker…

Thanks,
Larry

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well that puts hard primers out of the question, so check the following.
lube the trigger, couple of did you questions, 1 did you install the extension spring in the correct Direction, did you install the extension spring in the correct orientation ,(big eye loose on the thru pin lil lube,wrap is low and to the right for orientation)
I am OCD as hell, so usually dot lube all pivot and slide areas of pins, and locks, slick is better, pay particular attention to the striker lock and lock areas, lil dab will do you.
double check that striker operates smoothly.
as its not in my paw, i would have to WAG your orientation is flipped on extension spring. check it lube the points, and try again.
my usual benchmark is 1000 rounds on a factory gun before i change anything.so i know for a fact all points are broken in before i start making improvements. but like i said, i am OCD

Thanks for the input, I did already double check my work against the MCarbo video, from what I can see everything is installed correctly. I also lubed the trigger where it contacts the frame as per the install video.

I am wondering if the heavy duty APEX striker is a problem, thinking maybe springs were designed to work with the standard FN striker…

Thanks,
Larry

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Thanks,
Hoping MCarbo can make suggestions on where to start…

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how much heavier is the striker?

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if she striker has that much of a increase in weight, swap back to original springs on the heavier striker or swap back to the lighter striker with the mcarbo springs…

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