Gotta keep beating on it, the S&W pins are very tight on the FSB. Good thinking with the calipers, most folks believe it or not would just beat on them assuming that a TAPER PIN is actually straight. Gotta ask the question but.....you did pull out the gas tube right? Lol. Other than that I hope you are using a setup similar to a reaction rod to engage the barrel extension itself if it's that tight. Feel free to send a PM if you need anything, happy to help
Everyone takes a beating sometimes.
"Just rubberize that carp"
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