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Will the stock OEM spring work (17 rounds) or do I need to exchange spring for 22 round capacity? — 1 Answer
by
ZEEMAN,
from CA, United States Asked on December 15, 2023
Killer Innovations Sig P320X Magazine Extension(3.3)
Answered by
Killer Innovations,
Manufacturer
from WA, United States,
on August 20, 2025
Killer Innovations mag extensions are designed to work with your existing spring. However, if you have issues feeding or have a larger magazine than standard, you will need to upgrade to a +power mag spring for optimal function.
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