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.
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