Ramp And Throat
In 1996 I had Jim Hoag in Canoga Park Ca.do his magic on a then new Colt Series 80 Enhanced Gov. When it went in would not feed ball. It worked good after that, with hard ball. Not hollow points, not even Win.Silvertips.
I bought Wilson mags because everyone said they were great! Didn't work.
Well long story short, the only thing that really made it dependable was a Check-Mate mag. 8 round extended hybrid mag. feeds everything smooth!
Samething with a new Kimber Ultra Raptor only the 7 rd. mag.
And yes the ramps were polished to remove tool marks that the factory didn't have the time to do.