Load testing for my CZ527

[LRRPF52]

Usually I load 8208XBR, but this testimonial prompted me to load some CFE223 charges under some 123gn SMKs. 31.2, 31.3, 31.4, and 31.5gn all obtained nearly identical velocities of ~2525fps out of a 20". Apparently reaching a plateau. I infer I should not step to any higher charges.

That's only a net increase of .3gr, so it doesn't surprise me that your velocities are tight. There aren't a lot of scales that can accurately duplicate .1gr increments, especially in a contaminated environment, particularly with the presence of RF interference nowadays. It also might indicate an accuracy node for you. Work it up in .3gr increments and see what you get, always checking the speed increase relative to the charge weight. If you get an increase that exceeds 30fps, I would look at that as a likely ceiling.

When I did my pressure ladders with CFE, I was getting very consistent 12-21fps increases per .3gr of charge. I keep electronics with RF away from the load bench, and I'm pretty OCD about my charge weights. I didn't use a powder measure with those, but did them all by hand. My 31.2gr load that I produced is very accurate, proving so in a new Grendel shooter's hands at 500yds on a KYL plate rack, which he cleaned.