I normally say not to cut springs, but that is what you may have to do.
But, before cutting, purchase another. Should you cut too much off the original, you would then have a second that should work and keep your firearm functional.
Another thing to do is to make sure that the mag release is not "hanging" on something.
How much to reduce? It varies. If it is used as a carry piece, then I would prefer heavy to avoid accidental mag release. If used on the range only, check that holstering does not activate the button, and that it has enough to retain the mag.
"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
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