I use the Lee Universal Expander die. I set it a few years ago and keep it in a lock n load bushing so I just twist n go. Lot of folks use a powder thru expander die for a 30 Cal Carbine.rlandry6 wrote:How would I bell the case mouth with my setup. MyDillon would do it with the powder funnel, but I'm doing these on a single stage.smustian wrote:It is very possible that your case mouth was not deburred enough and the sharp edge was shaving the copper slightly. Since rechamfering the mouth resolved the issue you have your answer. Many people slightly bell the case mouth then run through a crimp die to straighten it back out. There is probably a 50/50 split on this board as to who uses a crimp die. You do what is best for you. If you decide to crimp I suggest getting a Lee Factory Crimp die and not using the crimp in the seater die. The LFC die will be easier to use and set up.
As for your original post on the 125 SST, I can't remember where I set COAL I think I wound up around 2.18 but not sure. I mostly shoot em thru my stick shift RARR and never tried to fine tune. They seem to be ok with the jump as it shoots under an inch at 100 yds.
FWIW I don't use a comparator for my Blackouts, especially ARs. Easier for me to work from initial loadings, pressure signs and COAL based on mags.