I have been shooting Swiss Vetterli's (M78 and M69) for a couple of years now. Both of my rifles shoot very well but I could never quite get that perfect 5 shot group, there was always a flyer or vertical string that ruined it. My brass is formed from .348, some was new, some was old brass used for 50-70, and the lengths varied. I made a trimmer on my lathe (a scaled copy of the WFT from Little Crow) and got it all to the same length, I also annealed all the brass. I loaded up my standard load of 18 grains of Alliant 2400, a modified Lee 310 grain bullet (reamed the mold to get rid of the gas check shank), home-made lube, sized to .431, and a CCI LRP 200. I also use a home made M-Die to expand the case mouth. I fired one fowling shot through the M78, then fired 5 shots on paper at 50yds. When I looked through the spotting scope I had to laugh as it was a one (ragged) hole group although not quite as pretty as I had imagined it, .79". I had a L to R 10sh MPH wind so that will be my excuse for now, will have to try again on a calm day.
Tom