Maybe I missed the memo, but I'm not seeing a mag problem. Sounds like they are getting into the chamber ok, just not closing the deal 100%.
I'm assuming an AR15 of some sort? 5.56/.223?
What kind of ammo? If your using steel cased ammo, try something else. If that fixes it, well there you go.
MSgt, USAF, Retired
NRA Life Member
The hardest thing to explain is the glaringly evident which everybody had decided not to see. - Ayn Rand