Definitely taper crimp. The amount of taper crimp will depend on your powder charge. Load six and shoot five, take out the sixth and measue the oal to see if the bullet is pulling out. If it is then you'll need a little more crimp pressure until the bullet does not move out. In my Lyman 50th Edition it's calling for 1.550" OAL, that'll be a good starting point. I load 160g LRN in 38 Short only and in my 38Special I shoot 125g lrn. Hope this helps.