I use a 420 gc cast bullet over 40 grains of IMR 4198, it gets 1630 fps.
Either of the 4198 powders burn clean and very accurate. This load is only 8 inches low at 200 yds, I loaded up some more test rounds tonight at 41.5 grains of IMR 4198, I think I should be able to get about 1700 fps without any strain on gun parts or shooter parts.
My rifle is a pre Remington Marlin GS, it gets under an inch at 100 yards with this load combo. This will be the boomer my son wants to use to get his first bear come spring here in Canuckieville.