How I do it I put in 50 primers at a time.Slide open the box so just 50 are showing holding the box turn auto prime up sidedown on the box make sure box is all the way in covering the primers and turn over.You might get one now an then that falls out.And if you have to flip some a GENTLE shake works best.As far as that #@$$#@ cover goes live with it
Don't turn box untill auto prime is on top
