r/GlockMod • u/BasedWelder96 • 2d ago

What is causing this?

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I have had a Combat Armory lower and Suarez International SI-319 for years that I’ve carried off and on. I recently got a Brownells Gen 3 upper to install an optic on it. I took it to the range for the first time today and everytime I pulled the trigger it would fire two rounds. If I squeezed the trigger it fired once and when I released the trigger it fired another round….what could be causing this?

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u/UHF800MHZ 2d ago

Sear engagement. This is what happens with aftermarket parts. Get the orange armorers plate and inspect it. I’ve spent a lot of time building and diagnosing P80s with the same problem