I suspect a lot of people may not use the collet correctly. Watch the RCBS factory video. Note also that Quinetics is selling an aluminum collar to increase the impact effect so fewer strokes are needed. It is demonstrated in this video needing just one hammer stroke. The puller without it is demonstrated here.
Looking at my shell holders, another important factor would be that some have a pronounced high primer channel while others have none. Those with the high primer channel would be much less likely to give the primer anything to strike against unless it were very high.
Looking at my shell holders, another important factor would be that some have a pronounced high primer channel while others have none. Those with the high primer channel would be much less likely to give the primer anything to strike against unless it were very high.