Re: No H450, what to use now in 7x57.
Don't load for a 7x57, but had the same problem with H450 dissapearing. I found that H4831 is almost Identical in preformance to H450, but I wanted to stay with a ball powder. After a while I was just about to give up finding a ball powder that had a burn rate the same as H450, until I stumbled upon Accurate Magpro. Magpro is slightly slower than H4831/H450, but it is also denser and therefor you can fit a heavier charge in the case before you run into a compressed load.