Have not been shooting much the last year or two and decided to clean up my brass and load what I can to keep occupied on the weekends after a few weeks of 10-14hour days working from home (my company makes ventilators and we ramping production 7x right now). Anyway I have SS tumbled and full lenth sized my brass (lapua .260, twice fired) in a redding neck bushing die on a coax. Went to trim cases in my giraud and found the case mouths do not want to fit through the die on the giraud trimmer. They fit fine in my wilson full length case gage. I can pop them through the trimmer orifice with pressure but then have to use a case holder on the bottom to pull it back out. (And considerable force).
So I started dicking around with the trimmer orifice to file/stone it out a little bigger. Even chucked up a piece of brass (that would not fit) into my drill press and put on some rubbing compound to see if i could polish the orifice a bit larger. (Worked great polishing the brass off the case end
).
I have a bin of old lapua 260 brass with loose pockets I keep for setting up the trimmer and annealer and happened to try one of those. They all fit in the trimmer orifice fine.
It seems my "recently" fired brass is all slightly bell mouthed. Not extreme as a berger 6.5 130 hybrid wont slide into the unsized neck. Both twice fired from my Surgeon with a Bartlien that has a tac-match chamber and the 7 fired lapua brass used in my Savage 10BA rebarreled with cheap eabco .260 barrel for my son (shoots great, just a really long jump to the lands). I am guessing it is something I am doing but cant figure out root cause.
I do use the TiN coated neck bushing and also the carbide bead through the neck. Do not neck trim but the lapua brass has been pretty consistent so has not seemed necessary. Brass fits and cycles through the rifles fine... this is probably only like a .001" - .002" diameter difference at the case mouth but really annoying since I cant easily use my giraud trimmer. It didnt use to be there. Any ideas what may be causing it?
So I started dicking around with the trimmer orifice to file/stone it out a little bigger. Even chucked up a piece of brass (that would not fit) into my drill press and put on some rubbing compound to see if i could polish the orifice a bit larger. (Worked great polishing the brass off the case end
). I have a bin of old lapua 260 brass with loose pockets I keep for setting up the trimmer and annealer and happened to try one of those. They all fit in the trimmer orifice fine.
It seems my "recently" fired brass is all slightly bell mouthed. Not extreme as a berger 6.5 130 hybrid wont slide into the unsized neck. Both twice fired from my Surgeon with a Bartlien that has a tac-match chamber and the 7 fired lapua brass used in my Savage 10BA rebarreled with cheap eabco .260 barrel for my son (shoots great, just a really long jump to the lands). I am guessing it is something I am doing but cant figure out root cause.
I do use the TiN coated neck bushing and also the carbide bead through the neck. Do not neck trim but the lapua brass has been pretty consistent so has not seemed necessary. Brass fits and cycles through the rifles fine... this is probably only like a .001" - .002" diameter difference at the case mouth but really annoying since I cant easily use my giraud trimmer. It didnt use to be there. Any ideas what may be causing it?
