Do you have occasional cycling issues that you can't resolve? Have you checked your mags? With metal mags, a slightly bent back plate may create interference, preventing the mag from rotating freely. With the newer polymer mags, the mag body itself may be warped and cause bad fit even with a good plate and also catch on the face of barrel while rotating. Tolerances are tight, and even a small problem here may cause cycling issues. Obviously the plates are easy to replace, but the mag bodies need a little work to fix.
I've encountered a few problematic mags in different calibers, this is what I do to fix them. All cycle flawlessly now.
Tools needed: a perfectly flat surface, 800 and 1500 grit sandpaper, a 2.5mm allen key, and a vise.
Hope this helps someone.
Checking for plate gap
View attachment 364794 A bent plate
View attachment 364795 Disassembling for inspection
View attachment 364796 Mag body
View attachment 364797 Yep, a warped mag body. This is actually not too bad, I've seen worse.
View attachment 364798 View attachment 364799 Sandpaper to the rescue...
View attachment 364800 Carefully sanding on a flat surface. You can see the high spots being sanded away as you progress. Finish with 1500 grit sandpaper.
View attachment 364801 View attachment 364802 View attachment 364803 Cleaned up
View attachment 364804 View attachment 364805 Perfect fit (with a new plate)
View attachment 364806 Thickness before:
View attachment 364807 Thickness after (total 0.1mm of material removed)
View attachment 364808