from what i can remember the cartridge expand as the chamber was hot after 4 shots, if you take to long to pull down the lever the cartridge might expand and stay blocked in the chamber, then you have to wait and take it out. that was the first and last time we used sako bullets for this rifle. i think american bullets will probably go better with an american rifle

like the Remington's and Winchester's. now im actually shooting 150gr Winchester and where i live (Mauritius island) they don't have 165gr in Winchester, but next season i might move to the core locks Remington as they have 165gr.
what in your opinion do you think will perform better the 150 or 165? knowing that we shoot both running and standing deers from a distance of 25 meters up to 400 meter even more sometimes.