IMR 7828 / 7 STW Question

[thunder12345+]

I have been loading Swift 150 grain Sirocco II with 81 grains of Reloader 25 also loaded with H1000 84 grains in my STW. I was going to try 7828 but never took the time to work up a load. Pressure can build quickly with certain powder and primer combinations.

 

[Keith1]

I had the same experience with 7828 but with a different caliber, a 300 Winchester and 180 grain Partitions. The 26 inch barrel was installed and long throated so that the Partition could be seated with an OAL length of 3.6 inches. The powder charge was 80 grains of 7828 with zero indication of excess pressure. When the 4 pounds of old 1980s powder was finished to my surprise the max load is now 76 grains. Something has really changed over the years.
Regards