Patchboy,
Just like burning gas in your car or truck when you buy it new.See which gas give's you better mileage
with what Brand and OCTANE .

Rifle's, you load 4 different brands of powder in different bullet weights and style.

I like Jack Daniels Black and other pepole like Jack Daniels Green...
When I use to drink!!!

After 6 or 9 rounds from each mentioned in the above advise and still have a problem... I would try,
7mm mag....For Sale Cheap!!!

I use nosler partions 140gr..H4895