I shot just a few of the prime 142 smk ammo. It was running around 3125 fps from my 27" bbl. I found that the 147 eld is aprx 2.864" touching the lands & my mag box will only hold 2.860" round loaded with a 147, so I will be ok for a while anyway. My issue is: I have donuts in the non-sized once fired cases. I'm not accustomed to dealing with donuts. Recommendations for an inside neck reamer? I assume that I should ream them before sizing, yes or no?
If the donuts are minimal, use a neck mandrel after sizing to push them out. If you need to neck ream there are lots of good ones. I personally like th L E Wilson, cause thats what I started with for a case trimmer. You can buy a reamer/cutter to the thousandths size you need and it fits in the same frame as the case trimmer.