I have a question about powders. TO thins point I have been using IMR 4350 with excellent results, however due to conditions beyond my control and the advice of some other shooters I am looking to change up powders and would like some advice before I spend my money. I am shooting a remington sendero in 300 win mag. I currently use winchester cases, federal 215M primers, 200 grain BTSP sierra GK's, with 68.0 prains of IMR4350. Recently my barrel has been shortened and recrowned, the IMR doesn't seem to be working for me anymore. I am curious to know if anyone has any experience with IMR 4831, H4831 & 4831SC, or Reloder22. Keep in mind I live in Northern Alberta and shoot almost all year round, meaning temp. changes from 30 degrees above zero to 30 degrees below zero (celcius).