No H450, what to use now in 7x57.

[VON GRUFF]

In my older Hornady (3rd ed) the powder for best results is H450 but as that is no longer available I was wondering what the collective wisdom would use instead. I had used the 139-140gn bullet in my previous 7x57's over Varget but have just finished a custom with a 25in x 9in twist bbl and had it throated to suit the heavier bullets. I have exceptable loads for the short to medium range but want to use the 168gn berger for a bit of stretch out work and using H4350 it runs out of the velocity - accuracy window at 2558fps for 3/4in at 100yd. I have two burn rate charts and one shows Rel 19 and N205 and the other shows IMR 4831 and N205 as being similar burn rate. The question is has anyone who had previously used H450 found a equaly well performing substitute pwder. If there is someone who has data for H4831 that performs better than H4350 that would be ideal for me as sourcing some powders here in New Zealand are easier than others. Gratefull for any insights.

Von Gruff.

 

[steve smith]

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.

 

[VON GRUFF]

Thanks Steve, the H4831 - H450 similarity has also been posted on another forum and as that is redily available here as ADI 2213 will see if that gets up to what H450 is supposed to give with the heavier bullets. Havent seen Magpro here as yet.
Von Gruff

 

[GaCop]

IMR4831SC short cut is identical in burn rate and meters well with the short kernals. I use it in my 30-06 with 150 grain Nosler's. Load density is around 96% in Lake City 67 Match brass at 56.3 grains.

Tom