you did use the spring and the long orange follower that came withthe extension, Right? with all magazine extensions, Especially longer ones I like to install them and then leave the magazine fully loaded for a couple of weeks to set the spring. Choate recommends that if you are going to store the gun with the magazine loaded you get 2 springs and periodically switch them out so that they do not get too weak.
I would not cut the spring. it will weaken a bit with use.
CPL holder since 1991, NRA Lifetime Member, DU Member, NICET certified
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