Powder query: Vectan SP powders are from SP2 (fastest) to SP13 (slowest), they list SP7 & SP10 for .223. SP10 is for bullet weight up to 55 grains with a starting load of 20.8 grains. SP7 is for bullet weight from 60 grains with a starting load of 20.1.
I have a nearly full tub of SP8, why isn't that or the SP9 listed? Is it unsuitable, or do those other two simply cover the range of bullet weights, so they don't bother listing this?
As far as I can find out sp8 was developed for 9mm
There is not a lot of info on Sp9 for 223 that I could find🙁
I would suggest staying with a more known powder for 223 such as N140 as there is a lot more info on that available.
Looking at the burn rates for vectan tu 3000, sp7 and tu 5000 against N133 to N140 you should be ok.
I would use tu 3000 and sp7 on the 55-60grn and tu 5000 on 69grn heads.
Don't mess about. Use published and tested load data.
https://www.xxl-reloading.com/2016-V...eloading-Guide
Click on the data sheet tab to get full load data for all calibres, but here is .223 rem