Don't blame the ammo yet.
I like to ensure that my recesses around the extractor are clean and free from debris.
I have had problems with 2 semi-auto's that required some real cleaning to correct the failure to eject.
Both of these semi's didn't get the cleaning they deserved. (tools, you know0.
I use minimum lube (no grease or anything thick) near the extractor recesses and expect that crud will build with everyday carry.
KG