Dialing in a C Sharps 1885 45-70 BPCR

[Kurt]

Cat three and less then two inches vertical at 400 yards is very respectable. make sure you have the load information well guarded so you don't loose it for this powder lot number. Developing loads I look at the vertical and not to much at the horizontal. Horozontal spreads for me is not correcting for wind and at times fat fingering or changing cheek weld and grip. Your vertical groups look very good for 400 yards in anybody's book.

I don't use sizing dies except the very first time with a new batch of brass. I have chambers I drew up and I use my reamers but they are designed for a PP only that don't need sizing for my chambers. I do have factory chambered rifles that will handle a GG bullet and for these I use a .45 short taper crimp die to get the neck diameter for a GG bullet or a PP for that matter in factory chambers. I can get the proper neck tension I want from one thousand or more with out having to use a expander plug or bushing die that might make a out of round mouth. I made a tapered plug that will fit a .38 to .50 caliber that will just flair the case mouth enough I need to get a bullet started with out shaving lead off the shank when seating with neck tension then back off the taper crimp die to knock the flair down just enough so the slight flair still on the case mouth scrapes the chamber wall. I know the taper is concentric so the case is held straight in the chamber. This is just important as getting the bullet run out to a minimum. I did this shooting bench rest and I carry it through for the black powder matches.
Yes this involves a little more time getting a uniform case length so everything is the same when the case is run through the sizing and flaring stages. I want to shoot my best at a match and if all this work falls together then if I fail shooting well it's my fault not my load or rifle or my spotter.