I carry a 669 in a Galco shoulder holster with the 2 magazines on the off side. I pulled one out the other day and it was covered with dust and lint. I think it would have locked in, but it might have taken a bit more pressure. I wiped both off with a towel with some lubricant on it and replaced them in the carrier.

I clean my carry guns monthly even if I don't shoot them. Part of that is taking the magazines apart and cleaning dust and lint out of them. I don't use lubrication because it attracts dust.

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Can open, worms everywhere.

Regularly check and clean my mags along with the firearm.
I also rotate mags, range mags to carry service and carry mags to range service to make sure they all work properly.

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Shut up and reload!

Good advice for all who concealed carry. Monthly maintenance, including magazines, and practice is a must!

Check your new mags for rough edges , metal shavings and grease .

... And don't forget the spit-shine!!!

I, too, do not use oil on/in my magazines. Dirt and **** will stick to it.
I also clean my holster's inside.

No oil inside or on the outsides of my magazines! I will use a little Renaissance Wax for corrosion protection, but no oil or grease. I do wipe down my carry weapon often, keeping magazines and firearm free of excess dirt can only aid in reliability.

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VCDL, GOA, NRA

Just got a new S&W pistol. Out of the box it gets cleaned along with the new mags. Both mags had a lot of powder residue inside (S&W must use the cheapest/dirtiest powder made) and I had to trim some excess plastic off the followers to prevent any dragging/alignment issues inside the mag body.
I use RenOil with Teflon to clean both gun and mags, being careful to get
residual oil out of the mag body (the Teflon gets into the mag walls and makes them slipperier). JMO
Frequent checks of the gun and mags for lint,dust,etc. and monthly takedown to check and lube is a good idea for any daily carry weapon.

Be SAFE and Shoot Often!