I personally own 2 220 swifts, one is a ruger and one a remington. The ruger will shoot any 55 grain bullet very well behind IMR4831. The best groups have been with 42.5 grains IMR4831, CCI benchrest primer, and 55 gr. Nosler ballistic tips. The remington on the other hand will shoot 52 grain and 60 grain bullets very well with IMR4064. I have expermitted with many different powders and primer combinations over the years and it takes time and patience trying to find the perfect load for a paticular rifle. Some reloaders will spent years trying to develop a load for a particular rifle. Chris