On my Gatling Gun test shoot that severe dent angle on the bullet had me wondering for a while.
Seems the load point of the stick mag has the bullet .062 overhanging the extractor(The circled area in the pic). So the bullet would drop and the rim would \'hang-up\' on the extractor by .062(Then Smasho). I machined the stick mag base \'bullet groove\' to a paper thin web at the front(it already was .032 thin). Then I made a .062 washer for the hinged door to move it forward so the bullet tip was even with the face of the barrel. I still had an overhang over the extractor, so I ground an angle on it to guide the bullet \'in\'.
The bolts have some slop to moving front to back, so check the for the worst case senario.(Two yellow lines show slop in bolt forward/rearward)
The circled yellow area was later ground at a 45 degree angle to guide the rim end \'in\' when the bullet dropped.