I know your pain! my Full Sized SR9 was also very stiff the first 4-500 rounds. I'm now closing on 1K through her, and i will say that as long as it's fed factory ammo or "Factory" reloads she just chuggs along...3" groups or less at 25 yds. from the rest...2" single holes at 10 yds. on shoot n C targets...
Practice working your slide and changing Empty mags! Also do some extra cleaning & lube work on your slide. I use Frog Lube or CLP on the internals, but i also use remington oil, both the wipes and the spray can....get some extra on your slide rails and you will notiuce the difference! Worked for me on both my LC9 & the SR!!! Good Luck!
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