I read all of the posts in this thread! WOW what a bad example of thread drift!
What ammo are you using?
What magazine?
Are the magazines from the same manufacturer?
Keep track of which magazine is causing the issue.
Sometimes it could be a combination of ammo and one magazine where the edge of the round nose is hitting the slide lock and catching the slide!
And then there is the possibility that you could be lifting the slide lock with your thumb during recoil!
Smiles,
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