I don't want to measure powder so I picked up a box of 777 pellets. I'm using 250gr. hornady sst's with 3 pellets. My grouping is around 3-4" @ 100 yards. Where I hunt a 150-200+ yard shot is more than likely to happen. Would changing bullet weight to 300gr. or say switching to 150gr. of pyrodex improve my grouping? Any suggestions would help. Thanks