Buffer tube detent pin was drilled too far back. About .060″. Didn’t notice this until after noticing that the buffer was getting gouged up.

MGI-buffer-tube-detent-pin-hole

MGI-buffer-tube-detent-pin-hole-buffer

MGI-buffer-tube-detent-pin-hole-custom-pin

MGI-buffer-tube-detent-pin-hole-custom-pin-install

MGI-buffer-tube-detent-pin-hole-custom-pin-installed