Maybe if I keep posting this people will quit saying the problem was the magazines.
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The problem is not the magazines.
None of my (4) mags would drop freely from my CSX if loaded with more than (6) rounds.
My son's magazines all drop freely from his CSX if fully loaded.
His magazines will
NOT drop freely from my CSX if fully loaded.
My magazines
WILL drop freely from his CSX if fully loaded.
The obvious conclusion then is that our CSXs' magwells were not the exact same internal dimensions, mine being tighter.
I fixed mine by filing down the magwell's high spots.
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Both mine & my son's CSX POI hit about 3" left of POA. Tapping the factory rear sight a pencil mark's width to the right fixed that.
I ultimately installed XS's DXT2 Big Dot Night Sights on mine for easier sight acquisition. (Seems my eyes have gotten two sizes smaller

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The safety lever could be a little bigger & the mag's spacer isn't their best idea but it doesn't bother me.
I quit counting but I've got over 700 rounds thru mine now.
And I do like mine & think it's a great compromise in size & firepower.
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Out of the box, before rear sight adjustment, 10yds off-hand.
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XS DXT2 Big Dot Night Sights
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