I have loaded thousands of rounds of 7 mag. One thing about the 7 mag is there is several different versions from different manufacturers. Long barrel, short barrel, 9 twist, 9 1/4 twist, 9 1/2 twist, freebored, tight bore and all of this you need to take into consideration. I really like the 4831 powder for a hunting/ accuracy load in freebored rifles like the Savages. Slower powders like Retumbo for the heavier bullets and non freeboard rifles. 7828 is also really hard to beat, It was years ago when this powder was specifically designed for the 7mm mag. H1000 is a good universal powder for the 7mm but it can be beat by a large margin. 4350 is the most accurate powder if you have the barrel to squeeze the accuracy out of it but you will give some velocity up for accuracy. If you do not get the results your looking for switch and try the 150 barnes. It shoots like gang busters in freeboard 7mm mags with a very stout load of h4831 and Win MAG primers. Let us know how it goes!