Put on your safety glasses and run them into the de-capper primers get upset when you hit them real hard on the other side but they will pop out no problem but I always were safety glasses and throw a rag over the die just in case, I've never had one pop but just in case ya know I like my eyesight. When I was neck sizing I normally just sized half the neck and all was fine, you can adjust your die and see the line on the case where it's being sized by looking at it. I shuold have my neck turning stuff today I'm gonna give neck sizing a try with my 308 but for the last 20 or so years I've not had any problems just neck sizing but after I try this neck sizing I may be a believer. Later,
Kirk
Kirk